Between ‘ perception ’ and understanding , from LeiBniz to Kant

In previous work I have argued that more care must be taken when discussing Kant’s views on ‘perception’ and ‘perceptual experience’, in light of Kant’s own technical use of ‘perception [Wahrnehmung]’ to pick out the mental act distinct from both empirical ‘intuition [Anschauung]’ and ‘experience [Erfahrung]’, insofar as Wahrnehmung involves  consciousness  of empirical intuition over and above the intuition itself, and insofar as this consciousness of the intuition itself is not yet empirical  cognition  of the object it represents.  In the present essay I argue, first, that Kant›s use of ‹Wahrnehmung› is continuous in key respects with how the term is used both among German translators of Leibniz and among the later Leibnizians themselves, insofar as they all also associate ‹Wahrnehmung› with the consciousness or apperception of sensory representation, rather than with the elementary sensory representation itself.  I show that this is so, despite the potentially misleading fact that Leibniz and his successors (following Descartes) use the French ‹perception› and Latin ‹perceptio› to refer to the more elementary sensory representation itself.  I also demonstrate a continuous commitment to the  imagination  and its synthesis playing a mediating role in between mere sensation and Wahrnehmung (apperception).  I then argue, finally, that Kant nevertheless departs from this tradition by decoupling consciousness and apperception per se -and hence, Wahrnehmung as well -from acts of  understanding,  precisely insofar as Kant means to distinguish the mental activity required for Wahrnehmung as mere empirical consciousness of representations, from what is required for empirical cognition of objects via concepts.


Clinton Tolley § 1. the proBLem of 'perception'
Much of the discussion of Kant's account of theoretical 'cognition [Erkenntnis]' and 'knowledge [Wissen]' over the past several centuries has (understandably) focused on the nature and significance of his distinction within 'representations [Vorstellungen]' between 'intuitions [Anschauungen]' and 'concepts [Begriffe]', in order to specify their relevant contributions to 'experience [Erfahrung]' and to cognition more broadly. Recently, however, it is becoming more widely recognized that Kant's account of theoretical cognition in general involves a much wider suite of representations than merely intuitions and concepts, and that many of these are involved in essential ways in the constitution of experience in particular. More specifically, closer attention is being paid to the distinctive role played in the constitution of experience by 'the power of imagination [Einbildungskraft] ', 'apprehension', 'perception [Wahrnehmung]', 'consciousness [Bewußtsein]', 'images [Bilder]', 'schemata', and even 'appearances [Erscheinungen]' themselves as the immediate though undetermined 'objects' of intuition (cf. KrV, B 33) -as all providing their own distinct, if complementary, contributions to experience and cognition, related to but separate from those provided by intuitions and concepts themselves. 1 All of these representations are singled out at key points (some even in the very section headings) in Kant's discussion of cognition in the first Critique for the separate contribution that they make in the process of allowing cognition itself to 'arise [entspringen]' from the 'unification [Vereinigung]' of intuitions with concepts (cf. B75-6). At the same time, however, these are all representations that Kant contrasts both with intuitions and concepts, on the one hand, but also with cognition itself and experience as well, on the other. Rather, these representations TOLLEY, C. all function as intermediate steps on the 'progression [Stufenleiter]' that transpires within our mind as it moves from the receptivity of intuitions by our 'sensibility [Sinnlichkeit]' to the cognition of objects through concepts by our 'understanding [Verstand] ' (cf. KrV,B 355;B 730;. One likely reason for the relative neglect of Kant's account of these intermediate steps between intuition and cognition through concepts is a persistent worry that Kant can have nothing informative to say about these in-between representations, given the sharpness with which he draws his initial distinction between intuitions and concepts. 2 Famously, against Leibniz, who 'intellectualized [intellektuierte] appearances', and also against Locke, who has 'sensibilized [sensifiziert]' concepts, Kant insists instead that appearances (along with the intuitions which initially 'give' them to the mind) and concepts each arise from 'two entirely different [ganz verschiedene] sources of representation', namely, our understanding and our sensibility (cf. KrV,B 327). The very idea that Kant himself would recognize any sort of representations 'in-between' intuitions and concepts, yet not reducible to either, might seem to threaten the familiar narrative of how Kant means to mark his break with the views of his predecessors. Nevertheless, as there is more than sufficient evidence that Kant himself not only accepts the existence of such intermediate representations but also accords them a crucial role in his account of experience and cognition itself, we must take up the task of articulating a more complex narrative which can account for their distinctness from both intuitions and concepts, while also showing how the overarching position continues to respect the original intuition-concept distinction itself.
This sort of representational irreducibility has been more widely recognized in the case of experience, since Kant is quite explicit that experience itself involves both 'the intuition of the senses' and 'a concept of an object ' (cf. KrV,B 126). There has been considerable debate, however, over whether Kant takes representations of the imagination (images, schemata) to be likewise 'in between' intuitions and concepts, representations which are not identical to either any intuition or concept, but which relate to, or some way involve, intuitions or concepts or both at once. 3 In the case of perception, by contrast, its very existence as a representational stage distinct from both intuition and experience has often gone unnoticed. 4 In previous work, I have provided the beginnings of an analysis of what Kant means by 'perception [Wahrnehmung]', drawing both on Kant's own texts, but also on the use of 'Wahrnehmung' in the writings of some of the more influential of his immediate predecessors (Wolff, Baumgarten, Meier, Tetens). 5 The preliminary results of this analysis indicate that 'Wahrnehmung' is almost uniformly used by Kant and his predecessors to pick out the state of becoming conscious of a sensory representation already present in the mind, rather than picking out either the sensory representation itself, or any act of judgment about (cognition of ) the objects of such representations. In Kant's terms, Wahrnehmung as 'empirical consciousness' of sensory representations (cf. KrV,B 207) lies between sensation and intuition as mere sensory 'representation [Vorstellung] ' (cf. KrV,, and experience as 'empirical cognition' of objects 'through' such consciousness of representations as is afforded in Wahrnehmungen (cf. KrV,B 218).
In the present essay, I want to take up two important further issues that have come to the fore during these historical-systematic investigations. The first is a growing appreciation of the potential for significant terminological confusion to arise due to the common use of the English term 'perception' to render not only 'Wahrnehmung' but also the earlier Latin 'perceptio' and French 'perception' -as used, for example, in the writings of Descartes and Leibniz. As I will show below, this translation practice becomes problematic because, already arguably with Descartes (cf. § 2) but especially in Leibniz's hands (cf. §3), 'perceptio'/'perception' do not pick out representational states which essentially involve consciousness. Rather, for Descartes and Leibniz, 'perceptio'/'perception' should be associated instead with the first stage of the progression identified above -namely, with mere sensory representation. In fact, as I will also show below (cf. § 4), when Leibniz's French works are translated into German, in the generation before Kant's Critical period, it is precisely these German terms ('Vorstellung', 'Empfindung') that are used to render the French 'perception', rather than 'Wahrnehmung'. Strikingly, 'Wahrnehmung' itself is used instead to render Leibniz's French 'apperception'. I will then show that this is likewise true of the German renderings of the Latin textbooks written by the Leibnizians (and others) that were especially familiar to Kant himself.
The second important issue that I will aim to address here concerns the nature of the role, if any, that is played, for Kant, by the understanding within 'Wahrnehmung' itself. Elsewhere I have argued in favor of the traditional view, against recent 'intellectualist' and 'conceptualist' interpretations of intuition, that, for Kant, the understanding is not already at work in the mere having of an intuition, nor are concepts contained in the content of intuitions. 6 To the extent that authors have discussed 'perception [Wahrnehmung]' at all in this regard, it has largely been under the assumption that it is equivalent in sense to 'intuition', and has largely focused on texts expressing Kant's commitment to 'synthesis' being involved in 'perception', which are then taken to be evidence that Kant thinks synthesis is involved in intuition itself. This latter point is then assumed to demonstrate the intellectualist thesis that Kant thinks the understanding is involved in intuition (because in perception), on the common assumption that all synthesis is an act of the understanding.
In the examination of Leibniz ( § 3) and the post-Leibnizians ( § 4) especially, then, I will also be concerned to trace out how the understanding's relation to Wahrnehmung (as Leibnizian apperception) is conceived of in the pre-Kantian historical context, to help set the stage for a discussion of Kant's own views on this relation ( § 5). The main conclusions on this front will be in some ways more complicated. On the one hand, it will emerge that the Leibnizian tradition ascribes a pre-apperceptive activity of synthesis (unification) to the imagination rather than the understanding. On the other hand, the tradition will also be seen to consistently distinguish this activity of the imagination per se from Wahrnehmung (apperception) proper, taking the latter to require not just the imagination but the understanding (intellect) as well. This is because, as apperception, it involves a kind of self-consciousness via reflection. When we turn to Kant ( § 5), We find that Kant also agrees to the following points: first, the imagination performs its own synthesis or unifying prior to apperception qua consciousness of representations, and hence prior to the understanding; second, Wahrnehmung, by contrast, constitutively includes consciousness and consists in a form of (empirical) apperception; and third, apperception itself is something 'higher' than either sense or imagination. What is also striking, however, is that compared with this tradition, Kant puts forward a sharper distinction between apperception itself and the understanding, with the former consisting only in the capacity for the consciousness of representations, and the latter being defined as the capacity for cognition of objects.
More broadly, I hope the following will help demonstrate that closer consideration of these terminological-conceptual issues will be absolutely crucial to keep in mind if we are to hope to properly understand the developments in early modern German philosophical psychology, and to uncover the points of genuine agreement and disagreement between Kant and his predecessors. In particular, the results of what follows will force us to be more precise in our assessment of the nature of Kant's alleged departure from Leibniz and the Leibnizians. My own conclusion (cf. § 6) will be that there is considerably more overlap than might otherwise have been expected, given familiar narratives about Kant's break with the Leibnizians. In drawing out these parallels, my efforts here in comparative history of cognitive psychology are meant to complement important recent work that has also sought to resist the familiar historicaldevelopmental narrative concerning Kant's break with his predecessors and instead draw Kant much closer to Leibniz on other key questions concerning the erkenntnistheoretische foundations of metaphysics, geometry, and the natural sciences -partly in order to help sharpen our appreciation of how much was already in place intellectually with Kant's predecessors, but also in order to help sharpen our sense of where Kant's innovations actually lie. 7 § 2. from perceptio to the inteLLect in descartes As should already be evident, Kant was not the first to propose a threefold division of the core stages in the development of psychical activity toward cognition. This perspective has a long and rich history, going at least as far back as Aristotle. At the outset of the Metaphysics, for example, Aristotle distinguishes (1) a basic level of 'sensation [aesthesis]', which is possessed by all 'living things [zoa]', from (2) a second level involving 'memory [mneme]' and 'imaginings [phantasiais], which is possessed only by some, from (3) a still third level involving 'art [techne]' and 'reasoning [logismos]', which only those of 'the human genus' possess, and which is responsible for 'experience [empeiria]' and ultimately 'science [episteme]' (I.1 980a1-981a1). This division is repeated at the end of the Posterior Analytics, where the three levels are also associated with stages in a process within the human soul, such that, within us, (1) sensation gives rise to (2) memory when the sensation 'persists', and then frequently repeated memories give rise to (3) experience itself, which is now said to make present 'the universal [tou kath'olou] in the soul', as 'the one from the many', and which involves 'thinking [dianoia]', which in turn makes possible art and science (cf. II.19 100a1-100b5).
Despite various attempts to escape core aspects of Aristotelianism, the basics of this threefold division persist well into the early modern period, as will be seen especially clearly below when we consider Leibniz's account of the mind. We can, however, see more than partial traces of this even in Descartes. Though he has been widely understood as challenging in particular the Aristotelian account of the psychical life of non-human animals, and though it has been common to assume that Descartes denies all psychical dimensions to non-human animals (viewing them as mere 'bêtes-machines'), it has recently been argued that Descartes not only retains certain key psychological distinctions from the tradition, but means to ascribe certain lower psychical capacities to animals after all. 8 Whether or not this is so about Descartes' view of animals, what is more widely conceded is that, at least for humans, Descartes retains something close to the traditional threefold distinction in his own differentiation between sensation, imagination, and intellection. 9 To begin to get an orientation toward Descartes' psychology, we can start by considering the cruder twofold psychological distinction that Descartes draws in his 1641 replies to the Sixth set of Objections to his Meditations, in order to narrow our focus on what is psychical (pertains to the soul or mind) rather than merely physiological (pertains to the body alone). This itself is important, since the first psychical stage (sensation) is itself seen to (somehow) arise from an earlier physiological stage of affections and impressions upon bodily sense-organs -a stage which, as Descartes notes here, also often goes by the name of 'sensing'. For this reason, Descartes thinks we should more carefully distinguish the following 'grades or degrees [gradus]' within sensing (I have added the lettering for ease of reference): [a] The first is limited to the immediate stimulation of the bodily organs by external objects; this can consist in nothing but the motion of the particles of the organs, and any change of shape and position resulting from this motion. [b] The second grade comprises all the immediate effects produced in the mind as a result of its being united with a bodily organ which is affected in this way. Such effects include the perceptions of pain, pleasure, thirst, hunger, colors, sound, taste, smell, heat, cold and the like, which arise from the union and as it were the intermingling of mind and body, as explained in the Sixth Meditation.
[c] The third grade includes judgments about things outside us which we have accustomed to make from our earliest years -judgments which are occasioned by the movements of these bodily organs. my ital.) To further clarify, Descartes then provides the following analysis of how these three 'grades' are involved in the sensory experience commonly described as 'seeing a stick': [a] [R]ays of light are reflected off the stick and set up certain movements in the optic nerve and, via the optic nerve, in the brain, as I have explained at some length in the Optics. This movement in the brain, which is common to us and the brutes, is the first grade of sensory response. [b] This leads to the second grade, which extends to the mere perception of the color and light reflected from the stick; it arises from the fact the mind is so intimately conjoined with the body that it is affected by the movements which occur in it. Nothing more than this should be referred to the sensory faculty, if we wish to distinguish it carefully from the intellect. [c] But suppose that, as a result of being affected by this sensation of color, I judge that a stick, located outside me, is colored; suppose that on the basis of the extension of the color and its boundaries together with its position in relation to the parts of the brain I make a rational calculation about the size, shape and distance of the stick: although such reasoning is commonly assigned to the senses (which is why I have here referred it to the third grade of sensing), it is clear that it depends solely on the intellect. my ital.) On Descartes' picture as it is elaborated here, we need to separate out three distinct 'grades' within what is commonly called 'sensing', and assigning each to a different capacity or power we possess.
[a] First, there is the physiological grade, consisting in 'movements' that arise in our bodily organs due to being affected by other moving bodies, movements which then are communicated through our nerves, and ultimately into our brain. [b] Second, there is the perceptual grade, consisting in 'perceptions' that arise as 'effects' in our mind due to the mind's being 'affected' by the aforementioned corporeal movements, though this affection operates only on our 'sensory capacity', without the involvement of our intellect. [c] Finally, there is the intellectual grade, consisting in 'judgments' (and 'rational calculations'), which also arise in our mind (rather than our body), but which are assigned to not to our sensory faculty but instead to our intellect.
This same threefold division, finally, can also be found in Descartes' later 1649 treatise, The Passions of the Soul: Those [perceptions] which we refer to things outside us, namely to the objects of our senses, are caused by these objects (at least when our opinion are not false). For in that case [a] the objects produce certain movements in the organs of the external senses and, by means of the nerves, produce other movements in the brain, which cause [b] the soul to sense them [les sent]. Thus when we see the light of a torch and hear the sound of a bell, the sound and light are two different actions which, simply by [a] producing two different movements in some of our nerves, and through them in our brain, [b] give to the soul two different sentiments [sentimens]. And [c] we refer these to the subjects we suppose to be their cause in such a way that we think we see the torch itself and hear the bell, and not that we sense [sentir] merely the movements coming from them. (AT XI.346).
Here Descartes aligns the 'perceptions' which are the 'effects' produced 'in' the mind with 'sentiments', i.e., things which are 'in the soul' and distinct from the physical objects responsible for bringing about the bodily movements of the first stage. Descartes also clarifies the immediate object of the sentiments/perceptions: the 'movements coming from' the physical objects, rather than these physical objects themselves. Finally, when we make judgments about things like torches and bells, the process is a mediated or indirect one of our 'referring' these 'sentiments' to outer objects, rather than just apprehending the objects directly.
If this establishes that Descartes embraced the broad distinction within psychical states between [b] mere sensing (having perceptions, sentiments; as opposed to [a] undergoing merely bodily affection) and [c] the intellectual activity of judging, what I now want to introduce is evidence that Descartes also embraces a further intermediate level or stage between mere sensation (as a form of perception) and intellection --on par, at least in broad strokes, with the level Aristotle took to be constituted by memory and imagination.
Though, throughout his writings, Descartes regularly distinguishes between 'sensing [sentire]', 'imagining [imaginari]', and 'intellection or understanding [intelligere]' (cf. Principia I.9 AT VIII.7; I.32 AT VIII.17), the exact nature of the imagination itself is not specified at length. 10 That imagining is distinct from understanding is clear from Descartes' discussion of the wax example in the 2 nd Meditation and his discussion of the chiliagon in the 6 th Meditation. In the 6 th Meditation Descartes also claims that it is through 'memory [memoria]' that certain mental contents that are first perceived by the senses (such as colors, sounds, tastes, pain) 'reach' the imagination (AT VII.74). This both implies the distinctness of imagining from sensing and also indicates at least partially something of the nature of what is involved in imagination over and above mere sensing: it is something which draws upon memory to supply itself with previous perceptions as its content.
A bit more on the intermediary role of imagination can be filled in from Descartes' early remarks in the Rules. In Rule 8, Descartes distinguishes the intellect from both 'sense [sensus]', 'imagination', and 'memory' as three other faculties which are able to help or hinder the intellect in its quest for 'science [scientia]' (AT X.398). In Rule 12, Descartes says a bit more about this division -though here Descartes is explicit that, for the most part, what he is here discussing under the heading of imagination and memory are actually parts of the body rather than capacities of the soul (cf. AT X.412-14). 11 Even so, this 'corporeal' imagination or 'fantasy [phantasia]' here is said to be a place where the 'common sense [sensus communis] fashions figures or ideas' and also a place where these ideas and figures can be 'retained', which is what we then call 'memory' (AT X.414). Here the imagination is given a more productive role, insofar as it supplies a new content (e.g., figure, shape) to what had been merely sensed (e.g., color).
Admittedly, Descartes' concern in the more familiar metaphysical works is predominantly with separating out the 'pure' intellect from the senses and the imagination, and demonstrating that genuine cognition can be obtained only through intellection itself. What is more, it is clear that Descartes would not be sympathetic with any Aristotelian-sounding claims that cognition via intellection itself always 'arises' from sense or imagination. Nevertheless, in his more physio-psychological works, Descartes does allow that, at least when the intellect means to 'examine' anything that is 'referred to bodies', our mind must first 'form' the 'idea' of it 'in the imagination', which is itself a process that gets going (at least paradigmatically) by first 'exhibiting [exhibenda] the thing itself to be represented by the idea in the external senses', as he puts it in the Rules (AT X.417; my ital.). 12 This is so, even if, as the 2 nd Meditation emphasizes, it is ultimately the intellect alone, rather than the imagination, which 'perceives' the real nature of the physical object (e.g. wax) in question. 13 Before moving on to Leibniz, we can return briefly to the question of Descartes' views on animals. For despite his disagreements with the Aristotelians, Descartes, too, seems to associate the grades of sensing from the Sixth Replies with a division among kinds of substances. It is clear from Descartes' physics that he accepts that all bodies (all corporeal substance) can communicate motion and hence 'contain' movements, and so (in principle) can undergo the first grade of 'sensory response'. Only beings with souls that have a 'sensory faculty', however, can undergo the second grade, since this consists in the arising of perceptions 'in' a mind. Finally, only minds with both a sensory faculty and an intellect can undergo the third grade, since this consists in the arising of judgments (rational calculations) in response to perceptions (sensations). Now, while it is clear that human beings can undergo all three grades of sensing, and while it follows that all bodies can undergo the first grade, there has been some disagreement as to whether, for Descartes, there are beings which can undergo merely the first and the second without being able to achieve the third grade (intellection). In fact, the Sixth Replies themselves give us at least some reason to think that Descartes would accept that non-human (non-'rational') animals ('brutes') are just such beings. To be sure, it is clear from these Replies (and elsewhere) that Descartes rejects the idea that brutes are able to think: 'the brutes possess TOLLEY, C. no thought whatsoever' (AT VII.426; my ital.). Even so, Descartes does here seem to allow that brutes are able to have sensations. This comes out when, in response to the charge that he assumes that the way that 'beasts operate' can be 'explained by means of mechanics without invoking any sensation [sensus], life or soul', Descartes insists on clarifying that what he mean to affirm is that such an explanation can go through 'without invoking thought [cogitatio]' -after which he explicitly acknowledges that 'I accept that the brutes have what is commonly called 'life', and a corporeal soul and organic sensation [sensus]' (AT VII.427; my ital.). 14 What is especially striking for our purposes, however, is Descartes' willingness to also ascribe a form of imagination and memory to animals as well -hence, psychical states on the second level of the Aristotelian cognitive-psychological progression. Though this is treated more thoroughly and directly in his physiological-psychological works, 15 even the 2 nd Meditation itself gives an indication of this. At the conclusion of the discussion of our cognition of the wax, when Descartes considers on which occasion we should be said to have the most 'perfect and evident perceiving of what wax is' (i.e., cognition proper), he again distinguishes our relation to the wax (1) through the 'external senses', (2) through 'what is called the common sense, i.e., the power of imagination', and then (3) finally through the acts of 'distinguishing' and 'judging' (AT VII.32). In again emphasizing, however, that it is only through the final sort of mental activity that we are able 'to cognize [cognoscere]' the wax itself, Descartes here also adds that it is only this third stage which 'is not possible without a human mind [humana mente]', remarking about the previous stages, by contrast: 'what of this is an animal not able to have' (ibid.)? § 3. from perceptio to the inteLLect in LeiBniz's psychoLogy While there is much more to say about Descartes' psychology on these points, the foregoing should suffice to bring out the broadly Aristotelian contours of the Cartesian account of the progression from (1) the initial psychological-perceptual (rather than physiological) stage of mere sensation, through (2) the collection and retention of such representations in the imagination (memory, 'common sense') and the 'fashioning' of 'figures and ideas' out of them, and on to (3) our intellectual recognition of physical objects (such as wax) through judgment and reasoning. What I want to show in the present section is the extent to which Leibniz, too, embraces this sort of threefold progressive model -while at the same time also acknowledging the manner in which Leibniz sees himself as departing from the Cartesians over the possibility that both (1) and (2) could obtain without (3). I will draw mostly upon two of Leibniz's late writings from 1714, the Principles of Nature and Grace and the Monadology.
In his Principles of Nature and Grace (PNG), 16 Leibniz distinguishes between three kinds of simple substances or 'monads': lifes, souls, and minds (cf. PNG § 1). A 'life [vie]' is a simple substance which is characterized by certain 'internal qualities' and certain 'actions' (cf. PNG § 2). The former are what Leibniz calls 'perceptions', which consist in 'the representation of the composite, or the external, in what is simple'; the 'actions' of the monad arise from 'appetitions' which are certain 'tendencies to go from one perception to another' and are 'the principles of change' in the monad (cf. PNG § 2). Leibniz also takes a life to be associated with a body (cf. PNG § 4). In fact, perceptions themselves 'represent' changes in the 'organs' of the associated body; these changes in organs, which result from the organs being 'adjusted', are what Leibniz calls 'impressions' (PNG § 4).
A 'soul [ame]', by contrast, is a life which not only has a body which undergoes impressions, as well as perceptions which represent them, but also has 'perception accompanied by memory [memoire]', or 'perception of which there remains an echo long enough to make itself heard on occasion' (PNG § 4; my ital.). It is this more complex sort of mental state which Leibniz calls 'sentiment [sentiment]' (ibid.). Leibniz takes this sort of mental state, and the soul which is capable of it, to be distinctive of 'animals [animaux]'. 17 Yet though sentiment, and animal souls more generally, therefore involves more complexity than mere perception and 'life' -as it also involves memory -even this further complexity does not yet bring into play anything specifically intellectual. More is required, thinks Leibniz, to 'raise' a soul 'to the level of reason', at which point it becomes 'something more sublime' and 'is counted among the minds [esprits]' rather than mere lifes or souls (PNG § 4; my ital.). Leibniz accepts that 'there is a connection [liaison] among the perceptions of animals which bears some resemblance to reason', though upon closer inspection he thinks we can see that 'this connection is only founded in the memory of facts or effects', and 'not at all in the cognition [connaissance] of causes' (PNG § 5; my ital.). Beyond mere perception (in life), and the repetition and connection of perceptions in memory (in souls), minds are able to engage in the further act of 'noticing [remarquer]' these interconnections and 'performing reflective acts', such that they are even capable of 'considering [considerer] what is called 'I'' -i.e., 'substance, soul, mind' itself (PNG § 5; my ital.).
Leibniz's name for this 'noticing' of perceptions is 'apperception': '[I]t is good to distinguish between perception, which is the internal state of the monad representing external things, and apperception, which is consciousness [conscience], or the cognition [connaissance] of this internal state' (PNG § 4). Leibniz's discussion here implies that only souls which are minds can attain this state: apperception is 'something not given to all souls, nor at all times to a given soul' (PNG § 4). It is because they are without these states that mere animals 'are called beasts [bêtes]' (PNG § 5). 18 Now, Leibniz signals that he takes his introduction of the middle stage of sentiment, between mere perception (sensation) and intellection (judgment, reason), and his introduction of the soul as the correlative intermediate type of monad, between mere life and mind, to distinguish his position sharply from the Cartesian doctrine of animality. At least as Leibniz understands it, the Cartesian position 'shocks common opinion' by 'refusing sentiment to beasts', such that the Cartesians 'believe that only minds are monads, that there are no souls in beasts, still less other principles of life' (PNG § 4; my ital.). The cause of this, Leibniz thinks, is that, in their philosophical reflection, Cartesians in general 'disregard' in the human case all of 'the perceptions that we do not apperceive' (PNG § 4), with sentiments forming a special class of these. On their view, rather than seeing animals as enjoying something like a 'prolonged stupor', in which there is a 'great confusion of perceptions', all of which are nevertheless pres-ent and prolongedly so (even if not themselves 'noticed' or 'apperceived'), the Cartesians see animals as being in a state of 'death', in which 'all perception ceases' (ibid.).
If we now turn to Leibniz's account of human psychology in the Monadology (M), 19 we can find the same sorts of distinctions at work, if with a slight change in terminology. Here too we find Leibniz describing monads as possessing both an 'internal principle' of change (M § 11) and also a 'diversity' of states in the monad as 'that which changes' (M § 12). The latter is again associated with 'perception' as 'the passing state which involves and represents a multitude in the unity' (M § 14). The former 'principle' is again associated with 'appetition', as 'the action of the internal principle which brings about the change or passage from one perception to another' (M § 15).
In the place of the term 'life', Leibniz here refers to the simplest monads (substances) as mere 'entelechies' (M § 18). While even these simplest monads possess a kind of 'sufficiency [suffisance; autarkeia]' such that they can be counted as 'automata', what distinguishes them from other kinds of more complex monads, such as souls in the proper sense, is that they do not possess any 'sentiment', with sentiment again being singled out as 'something more than simple perception' -namely, perception which is 'more distinct and accompanied by memory [memoire]' (M § 19). Here Leibniz also goes on to describe the activity of memory itself as involving the imagination (due at least in some cases to 'habit [habitude]') (M § 27), such that both perceptions and even sentiments too are reproduced in animal souls: they are 'led to have sentiments similar to those they have had before' (M § 26).
Also as in the PNG, while souls are therefore to be distinguished from mere simple monads by being capable of more complex states involving memory, imagination, and habit, they themselves are again to be distinguished from minds, on the basis of their lack of reason (M § 29). 20 Human minds come to have reason itself (and 'the sciences') through our 'cognition [connaissance] of eternal and necessary truths', and this cognition itself also eventually 'raises' us to 'cognition of ourselves and of God' (M § 29). This happens through further 'reflective acts' which 'enable us to think [penser] of that which is called me [Moi] and enable us to consider [considerer] that this or that is in us' (M § 30).
In both works, then, Leibniz distinguishes (2) an intermediate animal layer of sentiment, lying between (1) mere ('simple') perception and (3) the kind of reflexive consciousness and cognition that is distinctive of rational minds. As with Aristotle and Descartes, Leibniz too singles out the capacities of imagination and memory as what marks off this second layer from the first sensory though still representational layer of mere perception. While Leibniz therefore accepts that only rational minds are capable of (3) the reflective cognition that this or that state is in us, he continues to accept both that there are (1) states which can be 'in' a mind momentarily without being noticed reflectively, but also that (2) states can remain prolongedly present in the mind or even be repeatedly re-presented in the mind without being noticed reflectively. In other words, Leibniz seems to be working with a more generic distinction between (3) apperceived perceptions (perception with 'consciousness [conscience]' (M § 14)) and (1-2) non-apperceived perceptions. This seems to track a basic distinction between there being an internal representational state 'in us' -even one that is in us by having been reproduced in us out of our memory via imagination due to some habit -and our having a kind of 'consciousness' ('thinking', 'considering', noticing') of it as in us. 21 When Leibniz again criticizes the Cartesians in the Monadology, it is now more directly about their treatment of this more general class of non-apperceived perceptions: because Cartesians 'took no account of the perceptions that we do not apperceive', their account of animal life 'failed badly', such that they were led to believe that 'minds alone are monads and that there are no animal souls or other entelechies' (M § 14; my ital.). The Cartesians thereby (allegedly) fail to recognize not only (2) (animal) sentiment but also even (1) mere (simple) perception, neither of which per se (according to Leibniz) are cases of (3) apperceived perceptions. The Cartesians (again, allegedly) only allow for there to be perceptions 'in' us when we in fact have the kind of reflective intellectual self-cognition that Leibniz takes to be distinctive only of apperceived perceptions. 22 Now, while the foregoing establishes Leibniz's recognition of the Aristotelian division among types of psychical substances, and also his embrace of the idea that there is a progression among these substances, what is still to be shown is the parallel progression among psychical acts or states that Leibniz takes to obtain within the human mind itself. One such exposition is given in the Preface to Leibniz's New Essays; I have added the numbering to help make the progression salient: [1] [T]here is at every moment an infinity of perceptions in us, though without apperception and without reflection, that is to say, an infinity of alterations in the soul itself which we do not apperceive, because these impressions are either too small or in too great a number or too uniform, such that they have nothing sufficiently distinctive on their own, [2] but when they are combined In a well-known 1702 letter to Queen Sophie Charlotte, Leibniz gives more indication as to how the imagination in particular is involved in the second intermediate step of 'joining' or unifying perceptions: [S]ince our soul compares the numbers and shapes that are in colors, for example, with the numbers and shapes that are found by touch, there must be an internal sense in which the perceptions of these different external senses are found united [reunies]. This is called the imagination.... (G 6: 501) Here Leibniz echoes Descartes by contrasting the work of the imagination with that of 'the external senses': while the latter are what 'make us cognize [nous font connoistre] their particular objects, which are colors, sounds, scents, flavors, and qualities of touch' (G 6: 499), it is only the imagination as 'internal sense' that is able to 'unify' perceptions of particular qualities into more holistic representations by joining together either multiple perceptions from a single sensory modality or even join perceptions together from across several sense-modalities. To do achieve this unification, the imagination makes use of 'notions of common sense', such as shape or number, which strictly speaking are not contained in the elementary perceptions themselves (G 6: 501).

TOLLEY, C.
This merely sensible unification, however, is distinct from whatever act of the intellect is required to achieve the cognition of those objects (things) which are thereby represented through these perceptions. As Leibniz goes on to make clear in this same letter, it is only through 'the understanding [l'entendement]' that our soul is able to recognize substances, qualities (properties), causes, effects, actions, and so on, rather than simply have or unify perceptions which represent such objects (G 6: 502). Still, Leibniz claims that the work of the imagination is a necessary stage along the way to cognition via sensory representation, and is also necessary for the latter to be able to be taken up by the understanding in reasoning: 'particular sensible qualities are susceptible of explications and reasonings only insofar as they contain [renferment] that which is common to objects of several external senses and belong [appartenir] to the internal sense' (G 6: 501). 23 § 4. 'perceptio' as 'empfindung', 'apperceptio' as 'wahrnehmung': LeiBnizianism in transLation While (again) there is much more to say about Leibniz's own philosophical psychology, along with additional points of overlap and distance from Descartes, enough has been said to draw out a basic, if high-level, continuity in Leibniz concerning the threefold division and progression within human psychology: from (1) merely sensory representation ('perception'), to (2) the collection and unification of such representations via memory and imagination, to (3) the use of the intellect or understanding to 'apperceive' these representations and to judge or cognize objects (substances, things) on the basis of the previous two layers. What we must now turn to is the question of the transmission -and potential transformation -of this perspective from Leibniz to Kant.
One important point of information concerns the decisions made by German intellectuals in the first half of the 18 th century as they set out to forge a philosophical lexicon in German that would be best suited to capture the thoughts and concepts expressed by Leibniz in his French writings. These decisions on translation manifest themselves both in the direct translations of Leibniz's writings into German, but also in the emerging practice of providing German glosses (in the margins and the footnotes) to key terms in the Latin philosophy textbooks of the period -something which occurs in several textbooks that were very familiar to Kant himself. 24 I will therefore begin by looking to German translations of Leibniz's own works in the 1720s ( § 4.1), before turning (in § 4.2) to German glosses to the relevant terms which are provided in Latin textbooks written by philosophers influenced by Leibniz and familiar to Kant. Our focus throughout will be on tracking the German terminology chosen to articulate the Aristotelian threefold progression. To anticipate: two key results from consulting the Leibniz-translations will be the perhaps surprising terminological coordinations, first, between Leibniz's French 'perception' and the German 'Empfindung' (i.e., the German word now commonly translated in English as 'sensation') rather than 'Wahrnehmung' (the German word now commonly translated in English as 'perception'), and then, between 'Wahrnehmung' and Leibniz's French 'apperception'. These translational conventions will then be confirmed via consultation of the German glosses in the Latin textbooks.

Leibniz in translation
Perhaps the single most instructive text in this regard is the 1720 German translation of Leibniz's Monadology by Heinrich Köhler, published as Lehrsätze über die Monadologie (LM). We will focus our attention on how Köhler renders the key passages in the sections from the Monadology discussed in the preceding section, beginning with M §14. In this passage, in which Leibniz first introduces what he calls (in French) 'perception', 'perception' itself is rendered by Köhler as 'Empfindung oder Perception' -that is, first with the German word associated with sensation (emphasis is Köhler's), and then by giving Leibniz's original French 'perception', with Köhler signaling typographically that he is here including a foreign word. 25 In fact, Köhler adopts this method of providing Leibniz's words directly, either accompanying his choice of a German equivalent or (often) without any equivalent German given, throughout the rest of his translation. In the following sentence in M § 14, Köhler adopts the same convention, though this time he instead gives a Germanized Latin equivalent of Leibniz's French, writing 'Perceptiones oder Empfindungen' for Leibniz's 'perceptions' (again signaling typographically that 'Perceptiones' is a foreign word).
What is equally crucial to note about this same second sentence of M § 14 is how Köhler renders the terms Leibniz uses to point up his contrast with the Cartesians on the existence of 'perceptions that one does not apperceive'. For Leibniz's original introduction of 'apperception or consciousness [conscience]' in the earlier first sentence of M § 14, Köhler gives 'Apperception oder Bewust seyn', again reproducing 'Apperception' as a foreign word and then giving a German gloss on it, this time the German word associated with being conscious (or consciousness) (LM § 14). In the second sentence of M § 14, however, Köhler now chooses to align Leibniz's 'apperceive' with two German phrases: first 'sich bewusst sein' but then also 'wahrnehmen' (LM § 14). 26 Now, as we have already noted above, in other circumstances the latter German word might itself also be rendered in English as 'perception', but here this would make a mess of the passage. Not only would rendering both Leibniz's (French) 'perception' and 'apperception' by the single English 'perception' have the effect of completely covering over the crucial conceptual difference that Leibniz means to be tracking with his different French terms, but it would force us to express Leibniz's challenge to the Cartesians as a failure to acknowledge 'perceptions [perceptions] which one does not perceive [aperçoit]'. 27 What is more, as consultation with Adelung's Wörterbuch from the period helps to make clear, the use of the term 'Wahrnehmung' in the 18 th century is one that expresses not just a passive receiving (on the model of a Leibnizian 'perception') but rather a 'taking [Nehmung]' in which one is 'aware [wahr-]'. 28 Similar choices recur through the remainder of Köhler's translation. In M §21, for example, Leibniz's claim that 'when there is a great multitude of petites perceptions without any being distinct', the substance in question is 'stupified [étourdi]', gets rendered by Köhler as a claim about what happens when there is 'eine grosse Menge von kleinen Empfindungen' of the relevant sort (LM § 21). 29 Köhler also renders Leibniz's claims in M § 27 about imagination 'coming from [vient de]' particularly 'grand' or 'multitudinous' perceptions, in terms of the 'Einbildung' being 'awoken [erwächset]' by preceding 'Empfindungen' (LM § 26). Concerning apperception: in M § 23, Leibniz characterizes 'waking from stupor' as involving the fact that 'one apperceives [s'apperçoit de] one's perceptions'; Köhler renders the latter idea as the fact that one 'wahrnimmet seine Empfindungen und perceptionen wiederum' (LM § 22). 30 In M § 8, Leibniz makes the related claim that 'if simple substances did not differ at all in their qualities, there would be no way of apperceiving [s'apperçevoir] any change in things'; 31 this latter phrase, too, is rendered by Köhler as there being no way that one could 'in denen Dingen einige Veränderung wahrnehmen' (LM § 8).
What do we find when turn to the stage that Leibniz classifies as intermediate to perception and apperception -namely, the sentiment had by animals through memory and imagination? Interestingly, with respect to M § 19, where Leibniz first introduces the stage of sentiment, where Leibniz writes that 'sentiment is something more than a simple perception', here Köhler glosses 'sentiment' (which he includes and marks as foreign; cf. LM § 25) with 'Gedancke', or the German word for 'thought'. 32 As far as I can tell, this is the only place where he glosses 'sentiment' with 'Gedancke', but it is still worth noting that the idea Leibniz had in mind -concerning a mental state that includes something more than mere 'perception/Empfindung' -was something Köhler felt was akin to 'thought' rather than merely a product of the senses. 33 One final choice that is worth noting concerns Köhler's use of the German word 'Vorstellung', now typically rendered as 'representation'. In relation to M § 14,Köhler associates 'vorstellen' with what every 'perception' does (cf. LM § 14). This occurs as well in LM § 20: where Leibniz speaks not just of 'perception' but of 'distinct perception [perception distinguée]', here Köhler writes: 'deutliche perception oder Vorstellung'. 34

German glosses by post-Leibnizians
The foregoing puts into place one important intermediate piece of the puzzle which connects Leibniz's French terminology with Kant's eventual choices of German expressions to name the elements of his own version of the progression from sensory representation toward cognition. 35 What I now want to show is that a closely parallel set of correlations were continued among the next generation of philosophers trained in the so-called 'Leibniz-Wolffian' tradition, when they were faced with the task of rendering their correlative Latin expressions into the newly emerging philosophical German.
One important example is the 1757 fourth edition of Alexander Baumgarten's Metaphysica (1 st 1739), the text on metaphysics that Kant used in his lecture courses. From this fourth edition forward, Baumgarten began including German glosses on the Latin words for certain key concepts in metaphysics. These first steps toward linguistic coordination were then furthered substantially when a partially abridged German translation of the Metaphysica was completed by Georg Meier in 1766.
In the Metaphysica Baumgarten himself doesn't (to my knowledge) introduce 'wahrnehmen' as a gloss on any particular act of the soul, though he does offer 'das wahrzunehmende' as a rendering for 'that which is observable [observabilia] (phaenomena)' (cf. § 425). 37 In his 1761 Acroasis Logica, however -which Kant had in his library, 38 and which also continues the practice of providing German glosses on certain key terms -Baumgarten does use 'wahrnehmen', and his use likewise continues the tradition we saw emerging above. After having already aligned 'perceptiones' and 'repraesentationes' both with 'Vorstellungen' ( § 3), Baumgarten then uses 'wahrnehmen' in the German glosses, not for mere 'percipere', but rather for 'appercipere' and 'esse conscius'. The following Latin phrase from § 15: 'that which we distinguish from something else, we apperceive [appercipimus], we are ourselves conscious of it', is rendered: 'das stellen wir uns vor, das sind wir uns bewußt, das bemerken wir, das nehmen wir wahr' (ibid.). 39 Crucially, apperception itself is associated in Baumgarten's Metaphysica with acts of 'attention [attentio; Aufmerksamkeit]' (cf. § 628), which is itself identified as an act of the intellect which is directed toward representations of sense and imagination (cf. § 625).
Strikingly, something close to this set of conventions for Latin-German coordinationand the same threefold division between sense, imagination, and intellect -was also followed even by those philosophers who were explicitly critical of various aspects of the Leibniz-Wolffian programme. A particularly important example in this regard comes from Martin Knutzen, one of Kant's more influential teacher. In his 1747 Logica (L), Knutzen anticipates the practice of Meier and Baumgarten by providing German-language subject-headings for each of the sections of the Logica in the margins. In L §24, Knutzen first aligns 'to sense [sentire]' with 'to perceive [percipere] with the senses', which occurs 'when we represent [repraesentamus] something present to ourselves', such that an 'act of sensing [actus sentiendi]' is 'sensation [sensatio]'. After dividing sensing into external and internal forms (along roughly Kantian lines), Knutzen then defines 'the faculty of imagining, or imagination' as that which 'is able to reproduce in ourselves images of absent things previously perceived by the senses' (L § 24). In the margins, Knutzen summarizes the contents of this section in German as follows: 'was empfinden, die Empfindung, die Empfindungskraft oder der Sinn und die Einbildungskraft sei'.
In L § 27 Knutzen affirms the now-familiar thesis that the senses (sensations) are the 'foundation [fundamentum]' (in the margin: 'ground [Grund]') for the imagination -and then also adds that they are also the 'basis' for 'all our cognition [cognitio; Erkenntnis]'. In L § 29 Knutzen then also clarifies another task that the imagination is responsible for: in the course of reproduction or retention of previous sensations, it 'brings forth connected representations together [bringet verknüpfte Vorstellungen zusammen hervor]'.
As with the Leibnizians, it is only after introducing both sensing and imagining, and having spelled out their psychological ordering, that Knutzen introduces the 'intellect or understanding [intellectus; Verstand]' in L § 33. In L § 34 Knutzen begins to enumerate what the understanding adds: it is 'the faculty of attending, reflecting, abstracting, comparing, reasoning, etc.'. Its first act, however, is what Knutzen calls 'simple apprehension [apprehensio simplex]', 40 by which Knutzen means 'the act of mind whereby representations of objects of produced by the senses or imagination are contemplated [contemplatur] without affirmation or negation' -with Knutzen here clarifying that the contemplated 'representation itself in the mind is called perceptio' (L § 35). Knutzen's marginal German gloss here on 'apprehensio' itself, as this first reflective act of understanding itself (and so, rather than the 'perceptio' toward which such reflection is directed), is: 'wahrnehmen oder bewusst seyn' -i.e., of a piece with what we have seen above. § 5. Kant on the pLace of 'wahrnehmung' in the progression through the senses, the imagination, and apperception From the preceding consideration of the tradition in and after Leibniz, we have uncovered a common set of analytical divisions, along with a fairly consistent set of terminological alignments. More specifically, we have found a consistent alignment of 'Wahrnehmung' not with (1) the most elementary stage of sensation (Leibnizian 'perception'), nor even with (2) the secondary stage of reproduction and unification of sensations by the imagination and memory (Leibnizian 'sentiment'), but rather with (3) a third, higher, 'reflective' stage of becoming 'conscious' or 'aware' of sensation and imagination by the use of our understanding (Leibnizian 'apperception').
For readers of Kant, this particular threefold distinction should sound familiar, as it is cast in roughly the same terms (sense, imagination, apperception) that Kant himself uses in the Analytic of Concepts -both in the lead-up to the Transcendental Deduction, and then again throughout the A-Deduction and (though less prominently) in the B-Deduction as well -in order to characterize 'the three subjective sources of cognition' (KrV, A 97). What is more, as I will show below, there continue to be fairly precise parallels in the details of how himself articulates the distinctions between the contributions of these three 'sources' (cf. § 5.1). Seeing these parallels will in turn help make even less surprising the fact that Kant also follows the tradition in his own use of 'Wahrnehmung', associating it not with mere sensation (or intuition), or even imagination per se, but rather with a form of consciousness ('apperception') of these representations (cf. § 5.2).
Nevertheless, I will also argue that it is not clear that Kant follows suit with this tradition on all fronts. More specifically, I will argue that Kant goes beyond the post-Leibnizians in more clearly identifying (3) the stage of apperception (consciousness) per se as something that does not already involve the understanding or its concepts, characterizing it rather as something more like (1) sense and (2) imagination -i.e., as something which 'makes possible even the understanding' (A97; my ital.), without itself already being the understanding. I will show that this is what lies behind Kant's distinction between apperception per se and what at various points he calls 'the unity of apperception' ( § 5.3); only the latter, but not the former, should be identified with the understanding -or so I will argue below.

Sense, imagination, apperception in the Analytic of Concepts
Once we have the traditional threefold progression in mind, several things about Kant's own path in the Analytic of Concepts become slightly less mysterious, since it becomes evident that Kant is proceeding largely on the basis of a traditional conception of the psychologicaldevelopmental stages of representationality which are required to achieve the cognition of objects, by leading up to the use of understanding.
Consider, first, Kant's use of this threefold division in the introductory sections to the Analytic. In §10, in the course of specifying the 'clue [Leitfaden]' to the discovery of the pure concepts of understanding, Kant makes note of the kind of 'content' that the understanding will have given to it, so as to provide its concepts with 'a matter', and to thereby 'make a cognition out of ' this content (KrV, B 102). The first source of this content is one that comes as no surprise to readers of Kant -namely, the 'manifold of sensibility', which Kant here notes has been the subject-matter of the Aesthetic (as the science of sensibility). Yet Kant here also then introduces a further, though less commonly noticed, second source of content or matter, above and beyond mere sensibility -namely, the imagination. The addition of something from our imagination is necessary because of the way our understanding ('our thinking') is constituted: it 'requires that this manifold first be gone through [durchgegangen], taken up [aufgenommen], and combined [verbunden] in a certain way, in order to make a cognition out of it' (ibid.). This further activity is supplied by the imagination, in the form of what Kant here calls 'synthesis', as that 'alone' which 'properly collects [sammelt] the elements for cognitions and unifies [vereinigt] them into a certain content' (KrV, B 103). Now, though it is common to think (perhaps especially in the B-edition) that Kant assigns all synthesis to the understanding, 41 here Kant says explicitly that 'synthesis in general [überhaupt] is...the mere effect of the power of the imagination, a blind though indispensable function of the soul' (KrV,B 103;my ital.). The understanding is not what is responsible for synthesis as such, but (as Kant then goes on to say) is instead responsible for a further act: the 'function that pertains to the understanding' is 'to bring this synthesis to concepts' (KrV,B 103;my ital.). What is more, though synthesis by the imagination lies at 'the first origin of our cognition' and so is something 'without which we would have no cognition at all', it is only this subsequent activity of the understanding (of bringing synthesis to concepts) 'by means of which' we are 'first provided' with 'cognition in the proper sense [in eigentlicher Bedeutung]' (KrV,B 103;my ital.).
In the following paragraph, we then see Kant explicitly laying out the familiar threefold progression -from sense, to imagination, to understanding; I have added numbering to help make it more salient: [1] The first thing that must be given to us...for the cognition of all objects is the manifold of...
[sensibility]; [2] the synthesis of this manifold by means of the power of imagination is the second thing, but it still does not yield cognition.
[3] The concepts that give this...synthesis unity...are the third thing necessary for cognition of an object that comes before us (KrV,B 104) 42 When Kant returns to this progression toward cognition (viz. experience as empirical cognition) at the outset of the A-Deduction, the terminological parallel with the Leibnizians becomes even more salient: There are...three original sources (capacities or faculties of the soul) which contain the conditions of the possibility of all experiences, and cannot themselves be derived from any other faculty of the mind, namely, sense, the power of imagination, and apperception. (KrV,A 94;cf. KrV,A 115) And in this later passage Kant again separates out 'synthesis' as what 'is grounded [gründet sich]' on the imagination, with this being again distinguished from 'the unity of this synthesis', which 'is grounded' on apperception (as understanding) (ibid.). 43

Kant's use of 'Wahrnehmung' in the Analytic
Given this fairly direct inheritance from the tradition of the stages of progression toward cognition, it is perhaps less surprising that Kant also closely follows tradition in his technical use of the term 'Wahrnehmung'. For Kant, as for the Leibnizians, 'Wahrnehmung' picks out, not Leibnizian 'perception'/'Empfindung', but rather the higher-level act of becoming conscious of such elementary sensory representations. Now, Kant departs slightly from the tradition insofar as he introduces a further layer of analysis in between (1) sensation and (2) imagination -namely, what Kant calls 'intuition [Anschauung]', which consists of a manifold of sensations 'ordered' according to a form (cf. KrV,B 34). By being constituted out of sensations ordered according to a form, the resulting intuition itself has not just a single sensory quale as the object it represents, but a whole field of qualia that Kant names an 'appearance [Erscheinung]' (cf. KrV,. Hence Kant's descriptions of 'Wahrnehmung' likewise depart slightly from the Leibnizians, by referring both to the consciousness of sensation, and of intuition, and of appearances. In the other relevant respects, however, Kant's account parallels the Leibnizians quite closely. Kant, too, distinguishes Wahrnehmung from the original givenness of sensory contents: 'the first thing that is given to us is appearance, which, if it is combined with consciousness [Bewußtsein], is called Wahrnehmung...' (KrV, A 119-120; my ital.); 'The consciousness of an empirical intuition is called Wahrnehmung' (ÜE,AA 8: 217;my ital.). Kant also takes Wahrnehmung to depend not just on there being a manifold of sensibility given, but also on there being a synthesis of this manifold by the imagination. In contrast to Knutzen, however, Kant uses 'apprehension' to name this imaginative-synthetic act, rather than reserving it for the first operation of the understanding in contemplating a representation: 'There is thus an active faculty of the synthesis of this manifold in us, which we call imagination, and whose action...I call apprehension' (KrV, A 120). Still, Kant retains the basic idea that an act of imagination is required to 'make possible' the transformation of a merely given sensory representation that we have 'in' mind into something that is accompanied 'with consciousness' -i.e., into Wahrnemung: [B]y the synthesis of apprehension I understand the placing together [Zusammensetzung] of the manifold in an empirical intuition, through which Wahrnehmung, i.e., empirical consciousness of it (as appearance) becomes possible. (KrV,B 160) If I therefore make, e.g., the empirical intuition of a house into Wahrnehmung through apprehension of its manifold.... (KrV,B 162) Again, note that apprehension by the imagination is not here said to be identical with the 'empirical consciousness' (Wahrnehmung) that it 'makes possible'; rather it is said to be one of its conditions (cf. AA 22: 476;AA 23: 18).

Apperception vs. the unity of apperception
While the foregoing allows Kant to continue to keep faith with the tradition by assigning Wahrnehmung itself, not to the ('blind') imagination, but rather to a still higher capacity for 'consciousness', it is less clear, however, that Kant himself means to assign the act of becoming conscious to the understanding per se. As we have seen, for the Leibnizians, Wahrnehmung itself constitutes a kind of self-consciousness or apperception, insofar as it consists in a consciousness of one's own representational states (things 'in' us, parts (predicates) of our minds, etc.). Since the Leibnizians also identified the capacity for recognizing (thinking, considering) of oneself with the intellect (understanding), it was natural for them think of Wahrnehmung itself consists in the 'first', 'simple' act of the intellect.
What is especially striking, then, about Kant's own analysis in the Deduction, in light of this tradition, is Kant's further distinction between (a) the mere consciousness of one's state -Wahrnehmung, empirical consciousness, or what he also calls 'empirical apperception', which is made possible by through the imagination's synthesis of apprehension -and (b) the 'unity of apperception' or 'unity of consciousness', which is something further, and something that is brought about by a representation of the synthesis 'through' the pure concepts of understanding (KrV, A 119). 44 Keeping track of this distinction is important for our purposes because it is ultimately only 'the unity of apperception in relation to the synthesis of the imagination' which is said to be 'the understanding' -rather than the act of empirical apperception per se, let alone the imaginative-synthetic act of apprehension which makes (empirical) apperception (Wahrnehmung) itself possible (cf. KrV, A 119; my ital.; cf. AA 23: 18).
By drawing a distinction between consciousness and the conceptual representation of its unity, Kant thereby opens up room for the possibility that, as merely empirical consciousness (of parts, states of oneself, empirical apperception), Wahrnehmung itself does not itself involve any representation through the concepts of the unity of apperception. It is striking, then, to note that, though he explicitly includes consciousness in his definition of Wahrnehmung, Kant himself does not anywhere (to my knowledge) demand that the consciousness that is constitutive of Wahrneh-mung be one that includes the representation of the unity of this consciousness through concepts. Rather, the latter idea is introduced primarily in the context of the transition from Wahrnehmung (empirical consciousness of sensations; cf. KrV, B 207) to experience as empirical cognition of objects 'though' Wahrnehmungen (cf. KrV, B 218-219). 45 Indeed, at the outset of the Logic, Kant explicitly characterizes the understanding itself, not as the capacity for consciousness of representations, but as the 'capacity for cognizing an object by means of [sensory] representations' (KrV,. What, then, is the capacity for Wahrnehmung itself, if it is not the understanding? As far as I can tell, the main possibility that suggest itself is that Wahrnehmung is achieved by the 'capacity' or 'source' that Kant names in the A-deduction simply as apperception -rather than the capacity responsible for representing its unity. Indeed, in the Metaphysical Foundations of Natural Science, Kant explicitly identifies apperception as the 'capacity [Vermögen] for consciousness' (MAN,AA 4: 542). Furthermore, the distinction between consciousness and apperception, on the one hand, and the understanding, on the other, is anticipated in Kant's notes from the 1770s. In Reflexion 410, for example, Kant notes that 'consciousness belongs to the higher capacity, but not as a necessary condition to the understanding' (AA 15: 166). To be sure, this would be to introduce a sharp distinction between apperception per se and understanding, which is admittedly not at all a commonplace among readers of Kant, but the foregoing has already suggested the need for this sort of distinction. And note once again that in the A-deduction apperception per se is classified along with sense and imagination as a 'source' that 'makes possible' the understanding (cf. KrV, A 97), rather than being identified with it.
Especially in light of these comments from the lectures, we might also expect Kant to more explicitly broaden the set of psychical states that are available to animals souls which do not possess an understanding, to include not just sensation, intuition, and imagination, but also Wahrnehmung itself as empirical apperception. 46 To my knowledge, in his published writings Kant doesn't ever explicitly ascribe this capacity to animals, but he seems to do just this in the notes from his lectures on logic compiled by Jaesche (cf. Log, AA 9: 64 ff.) as well as in his correspondence.
In his logic notes, Kant again draws the distinction between mere 'representing [vorstellen]' and 'representing with consciousness', and again identifies the latter with 'wahrnehmen', 47 before contrasting both of these with 'cognizing'. Strikingly, he also here notes a still further level of psychical activity, this time in between Wahrnehmung (consciousness) and cognition -namely, 'to be acquainted [kennen]' with something. What is especially of interest for our purposes, is that he here ascribes the capacity to be acquainted to animals -and hence, by implication, it would seem, both the lower capacities for mere representing and for Wahrnehmung, too (Log, AA 9: 65).
To this compare Kant's remarks in a 1789 letter to Herz, describing what would take place 'if, in thought, I make myself into an animal'. Here he suggests that, as a mere animal, the representations in us would not only still 'be combined [verbunden] according to empirical laws of association' but that I could still 'be conscious [bewußt] of each individual representation' (Br, AA 11: 52 ff.) -i.e., I could still enjoy what Kant calls elsewhere 'Wahrnehmung', and a form of empirical apperception (consciousness of my own state). What would not be possible as a mere animal, Kant here suggests, is the further consciousness of the 'relation' of an individual representation to 'to the unity of representation of their object, by means of the synthetic unity of apperception', which Kant here takes to imply that I would not be able to 'cognize' anything about myself or even about my state (ibid.; my ital.). In other words, I would have empirical apperception without understanding. § 6. concLusion: LeiBniz, Kant, and the progression from sensiBiLity to understanding Though (as with the previous sections) there is much more to be said about Kant's cognitive psychology and its relation to that of his predecessors, 48 I hope the foregoing will suffice to have made an inroad on the following three points about Kant's own views. The first concerns the continuity of Kant's views with his predecessors on the separation of both (1) sensibility and (2) imagination from (3) the understanding. All sides agree not just that (a) there is a primitive layer of representationality in the soul which does not involve the understanding or concepts (mere representation, sensation, 'perceptio'), but also that (b) there is a further intermediate level of representational states from the imagination, 'in between' mere representation by the senses, and cognition by the understanding through concepts, and, finally, (c) that while these intermediate imaginative states involve a kind of unifying (synthesis) of representations, this too does not involve the understanding.
The second point concerns the considerable continuity across the period in the use of the term 'Wahrnehmung', as marking a new level of psychical activity over and above both sensory and imaginative representation (Leibnizians: perceptio, imaginatio; Kant: Empfindung, Anschauung, apprehensio). Rather, Wahrnehmung is uniformly understood as involving the consciousness of sensory and imaginative representation. The third point concerns difference rather than continuity, on the relation between consciousness (apperception) and understanding. Kant officially expands the pre-intellectual reach of the mind so as to now include not just sense and imagination (apprehension), but also a form of empirical consciousness (Wahrnehmung, empirical apperception) of one's representations -with the understanding (pure concepts, cognition) coming into play only afterwards, in the achievement of cognition of objects by the representation through concepts of the 'unity' of such representations in consciousness. 49 The immediate 'object' of Wahrnehmung is a representation (sensation, appearance), and so something 'subjective', in the sense of being 'in' the mind. Kant thinks Wahrnehmung, as an achievement of mere apperception, must be contrasted with cognition proper (e.g., in experience) as the achievement of the understanding, since only the latter allows us to recognize whatever thing is (objectively) represented by the representation, rather than merely attending to the representation itself. 50 VENDLER, Zeno (1971), "Descartes on sensation", Canadian Journal of Philosophy 1: 1, pp. 1-14.
WARDA, Arthur (1922 [Erfahrung]', insofar as Wahrnehmung involves consciousness of empirical intuition over and above the intuition itself, and insofar as this consciousness of the intuition itself is not yet empirical cognition of the object it represents. In the present essay I argue, first, that Kant›s use of ‹Wahrnehmung› is continuous in key respects with how the term is used both among German translators of Leibniz and among the later Leibnizians themselves, insofar as they all also associate ‹Wahrnehmung› with the consciousness or apperception of sensory representation, rather than with the elementary sensory representation itself. I show that this is so, despite the potentially misleading fact that Leibniz and his successors (following Descartes) use the French ‹perception› and Latin ‹perceptio› to refer to the more elementary sensory representation itself. I also demonstrate a continuous commitment to the imagination and its synthesis playing a mediating role in between mere sensation and Wahrnehmung (apperception). I then argue, finally, that Kant nevertheless departs from this tradition by decoupling consciousness and apperception per se --and hence, Wahrnehmung as well --from acts of understanding, precisely insofar as Kant means to distinguish the mental activity required for Wahrnehmung as mere empirical consciousness of representations, from what is required for empirical cognition of objects via concepts.  Sellars 1978 andeven earlier Heidegger 1928. For appearances as distinct from both intuitions and concepts, see Tolley forthcoming. For earlier, similarly broadly psychological approaches to Kant's account of cognition and experience, see Sellars 1968, and Kitcher 1990, Waxman 1991, and Brook 1994 2 This sort of worry is especially common in relation to Kant's doctrine of schemata, for example, which is supposed to function precisely as a sort of go-between with respect to intuitions and concepts (cf. KrV, B 177 ff.).
3 Compare Matherne 2014, and Stephenson 2015 Cf. Tolley 2017 and Tolley manuscript-a and manuscript-b. For recent failures to acknowledge the importance of the distinction between intuition and perception (which in turn vitiate their arguments for conceptualism about intuition in particular), see Griffith 2011;Land 2011;Gomes 2014. (This is also true of 'empirical consciousness' as a distinct general category of representation from 'empirical cognition'.) This distinction is also neglected in McLear's earlier writings, though more recently he has begun to recognize its significance (and the significance for keeping track of the intuition/perception distinction for adjudicating the debates about Kant's alleged conceptualism); cf. McLear 2014.