Eve-Lyne Perron
LEIBNIZ ON HUMAN AND ANIMAL APPERCEPTION
Object-Based and Process-Based Interpretations
Medieval and Early Modern Philosophy
Julia Jorati / Dominik Perler / Stephan Schmid ( eds.)
Eve-Lyne Perron
Leibniz on Human and Animal Apperception
Object-Based and Process-Based Interpretations
Schwabe Verlag
An earlier version of this work, titled Leibniz on human and animal apperception : object- and process-based analyses, was submitted and defended on 12 October 2022 at the Faculty of Arts and Humanities of Humboldt-Universität zu Berlin. The committee consisted of Dominik Perler ( first reader ) and Christian Leduc ( second reader ). It was chaired by Geert Keil, dean of the Faculty of Arts and Humanities.
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§
§ 1 Summary of the controversy reduced to formal arguments
§ 1.1 The classic consistency problem
§ 1.2 The new consistency problem
§ 1.3 Bringing the two strands together
§ 2 Leibniz’ s relevance for contemporary research on animal cognition
§ 2.1 Perception as representation
§ 2.2 The distribution of lower cognitive faculties
§ 2.3 The distribution of higher cognitive faculties
§ 2.4 Conclusion
Annex 1 12 possible readings of the Principles § 4
Annex 2 Occurrences of the terms ‘apperception’ and ‘reflection’ in the New Essays, Theodicy, Principles, and Monadology
Annex 3
Acknowledgments
I followed in logic 101 – if p is a condition of q, one can infer ‘if not q, then not p’, but one cannot infer ‘if not p, then not q’. Sadly, I cannot infer that without such and such person, I would not have written this dissertation. I can still surmise, however, that without such and such person, I might not have written it.
Among those people, I would like to thank, first and foremost, my supervisor Dominik Perler. His constant support, insightful feedback, and relentless optimism definitely helped me improve my drafts. For their support and feedback, I would also like to thank my second reader, Christian Leduc, as well as my editor at the Schwabe Verlag, Christian Barth.
I was fortunate enough to receive feedback from several other people and would like to express my gratitude to Ursula Goldenbaum, the editors of the Medieval and Early Modern Philosophy series ( Julia Jorati and Stephan Schmid ), the participants of the colloquium for theoretical philosophy at Humboldt-Universität zu Berlin ( Han Thomas Adriaenssen, Jean-Pascal Anfray, Elena Baltuta, David Bartha, Sebastian Bender, Patrick Connolly, Luce De Lire, Thomas Harb, Julia Jorati, Anastasia Kopylova, Lena Kreymann, Nick Küspert, Vili Lähteenmäki, Fabio La Stella, Can Laurens Löwe, Kay Malte Bischof, Jennifer Marusic, Hannes Ole Matthiessen, Nicola Polloni, Anat Schechtman, Giorgi Tadumadze, Gabriel Watts, Ramona Winter, Zhaohao Kang ), the participants of the Atlantic Canada Seminar in Early Modern Philosophy, the Leibniz in Ligerz workshop, the Séminaire québécois en philosophie moderne, and the 9th and 10th Princeton-Humboldt Graduate Conferences in Philosophy ( especially Hao Dong and Thomas Lambert who provided me with detailed comments ). The participants in Jeffrey Verhey’ s writers’ group, although coming from different disciplines, also provided me with helpful feedback.
I would also like to thank the following people who, in different ways, contributed to this project : Jorge Castillo, Mireille Cyr, Sonja Feger, Christopher Gutland, Eva Henke, Marlene Kienberger, Anastasia Kopylova, Alexandra Makurova, Tzvetomila Pauly, Valérie Perron, Marine Picon, Céline Poirier, Tobias Rosefeldt, Martin Steffens, Margarethe Steffens, Lina Xu, and the Montreal writers’ group.
Of course, all of this would not have been possible without the small bits of paper that we, in our societies, use to obtain the necessities of life. I give my thanks to the institutions that provided me with these bits of paper : the Carl und
Max Schneider-Stiftung, the Social Sciences and Humanities Research Council of Canada, and the Elsa-Neumann Nachwuchsförderung ( for a scholarship I had to decline ). I am also grateful to the Deutsche Gesellschaft zu Montreal for a publication grant. For their help during the application process, I would like to thank Christian Barth, Gilbert Mclaughlin, Rüdiger Matz, Douglas Moggach, Valérie Perron, Philipp Schwab, and Lawrence Wang.
Abbreviations
A Sämtliche Schriften und Briefe. Ed. Deutsche Akademie der Wissenschaften. Darmstadt, Leipzig, Berlin : Akademie Verlag, 1923 ff. Cited by series, volume, page.
AG Philosophical Essays. Ed. and trans, by Roger Ariew and Daniel Garber. Indianapolis, Cambridge : Hackett, 1989.
C Opuscules et fragments inédits de Leibniz. Ed. by Louis Couturat. Paris : Felix Alcan, 1903.
DB The Leibniz-Des Bosses Correspondence. Ed. and trans, by Brandon C. Look and Donald Rutherford. New Haven, London : Yale University Press, 2007.
DM Discourse on Metaphysics.
DV The Leibniz-De Volder Correspondence. With Selections from the Correspondence Between Leibniz and Johann Bernoulli. Ed. and trans, by Paul Lodge. New Haven, London : Yale University Press, 2013.
GM Leibnizens mathematische Schriften. Ed. C. I. Gerhardt. Berlin, Halle : A. Asher, H. W. Schmidt, 1849 – 63. Cited by volume and page.
GP Die philosophischen Schriften von Gottfried Wilhelm Leibniz. Ed. C. I. Gerhardt. Berlin : Weidmann, 1875 – 90. Reprinted Hildesheim : Georg Olms, 1996. Cited by volume and page.
Huggard Theodicy : essays on the goodness of God, the freedom of man, and the origin of evil. Ed. and trans, by Austin Farrer and E. M. Huggard. London : Routledge & Kegan Paul Limited, 1951.
Idea What Is an Idea ?
LA The Leibniz-Arnauld Correspondence. With Selections from the Correspondence with Ernst, Landgrave of Hessen-Rheinfels. Ed. and trans, by Stephen Voss. New Haven ; London : Yale University Press, 2016.
Langley New Essays Concerning Human Understanding. Ed. and trans, by Alfred G. Langley. New York : The Macmillan Company, 1896.
Loemker Philosophical Papers and Letters. Ed. and trans, by Leroy E. Loemker. DordrechtHolland : D. Reidel Publishing Company, 1969.
LS Leibniz and the Two Sophies : The Philosophical Correspondence. Ed. and trans, by Lloyd Strickland. Toronto : Iter Inc. & Centre for Reformation and Renaissance Studies, 2011.
M Monadology.
Method On the Method of Distinguishing Real from Imaginary Phenomena.
MKTI Meditations on Knowledge, Truth, and Ideas.
MPW Leibniz. The Monadology and Other Philosophical Writings. Ed. and trans, by Robert Latta. London : Oxford University Press, 1898.
NE New Essays on Human Understanding.
NI On Nature Itself.
NS New System of Nature.
PNG Principles of Nature and Grace.
PS Philosophische Schriften. Band 5. Zweite Hälfte. Die Briefe der zweiten Schaffensperiode. Briefe von besonderem philosophischen Interesse. Ed. and trans, by Werner Wiater. Darmstadt : WBG, 2013.
PT Primary Truths.
RB New Essays on Human Understanding. Ed. and trans, by Peter Remnant and Jonathan Bennett. Cambridge : Cambridge University Press, 1996.
SD A Specimen of Dynamics.
Souls On the Souls of Men and Beasts.
Strickland The Shorter Leibniz Texts. A Collection of New Translations. Ed. and trans, by Lloyd Strickland. London, New York : Continuum, 2006.
Theo Theodicy.
W Leibniz : Selections. Ed., by Philip P. Wiener. New York : Charles Scribner’ s Sons, 1951.
WF Leibniz’ s ‘New System’ and Associated Contemporary Texts. Ed. and trans, by Roger S. Woolhouse and Richard Francks. Oxford : Clarendon Press, 1997.
Introduction
At this very moment, you are aware of this sentence. Perhaps, you are also aware that you are aware of reading these sentences. Perhaps, your cat Socrates is looking over your shoulder as you read, and he is also aware, in a sense, of the same sentences. One would readily grant, however, that Socrates the cat cannot be aware of these sentences as you are. In fact, it seems like we are here dealing with three very different forms of awareness :
1. The awareness of an object ( a sentence, a thing, an event, etc.).
2. The reflexive self-awareness of the subject perceiving the object ( which can be formulated as ‘I am aware of a sentence, a thing, an event, etc.’).
3. Animal awareness.
This study aims, broadly speaking, at disentangling these three forms of awareness.
It aims, more specifically, at disentangling these three forms of awareness in the philosophy of Gottfried Wilhelm Leibniz.1 This universal genius is famous, among other things, for having coined and introduced the concept of apperception in philosophy.2 It is interesting that, even though he coined the term, he did not clearly define it.3 He seems to have used it, to borrow Heidegger’ s metaphor, like a carpenter uses a hammer without reflecting on what it is. Leib-
1 For an overview of Leibniz’ s life, works, and philosophy, see Look (2020 ). For a more detailed exposition of his life and works, see Antognazza (2009 ). For a more detailed introduction to his philosophy or a handbook, see Laerke, Leduc, Rabouin (2017 ), Look (2011), or Rescher (1993 ). For a critical introduction, see Russell (1996 ).
2 The concept has come to crystallize around more than one philosophical theory ( and even psychology ) ( see Lange 1912 ). We know it, most prominently, from philosophers such as Kant, Wolff, and Husserl for whom it points to a kind of self-awareness. It is interesting that, for Leibniz, it does not so clearly point to self-awareness ( more below ).
3 It is in his New Essays that Leibniz introduced the term ‘apperception’. Its first occurrence is in the preface : “Mais outre, que personne peut assûrer par la seule raison jusqu’ où peuvent estre allées nos apperceptions passées [ ] outre cela dis-je pourquoy faut-il que tout nous soit acquis par les apperceptions des choses externes [ … ]?” ( AVIvi 52 – 53 / NE Preface ).
In the midst of Leibniz’ s defence of innate ideas, the reader is informed of the existence of “past apperceptions” as well as “external apperceptions” while Leibniz lays the emphasis, ironically, on what is not apperceived ( more in chapter 2 § 4 ).
niz’ s commentators, on the other hand, have attempted to define the concept of apperception based on how Leibniz uses it. For some of these commentators, apperception points to ( mere ) awareness. For others, it points to reflexive selfawareness. According to the former, animals might be endowed with the faculty of apperception. According to the latter, they cannot ( more below ). In other words, it is nebulous what apperception means and whether animals have it or not. What I propose, in this study, is to zoom in on Leibniz’ s concept of apperception to better distinguish awareness, reflexive self-awareness, and animal awareness from one another.
Provided that our goal is to better distinguish these three forms of awareness, isn’ t it misguided to focus on a concept that was not clearly defined ? A concept that even seemingly conflates the three forms ? Admittedly, if Leibniz did use the concept of apperception like a carpenter, handling awareness here and reflexive self-awareness there, animal awareness here and human awareness there, without reflecting much on what these conceptual tools mean, our approach would be misguided. My assumption, however, is that Leibniz did not philosophize in this way. Even though he seems to have used the term unreflectingly, I assume that he did not. Even though his concept of apperception seems to conflate the three forms of awareness, I assume, once again, that it does not. In fact, my working hypothesis is that Leibniz’ s theory of apperception appears to be hopelessly confused and complicated simply because it reflects the fact that awareness is a complex phenomenon. I believe to have confirmed this hypothesis, and by the end of this study, the reader will hopefully understand my grounds.
To recapitulate, this study aims to differentiate the phenomena of awareness, reflexive self-awareness, and animal awareness in Leibniz’ s theory of apperception. In the remainder of this introduction, I shall first expose in more detail what is or seems to be so problematic with Leibniz’ s concept of apperception (§ 1). Then, I shall review the extant solutions to this “problem” in the scholarship (§ 2 ). I shall then present my own approach (§ 3 ) as well as the methodology (§ 4 ) and structure of the study (§ 5 ).
Two notes are incumbent before moving on to § 1. First, the study focuses specifically on the aforementioned phenomena in Leibniz’ s theory of apperception. Although it is not deprived of systematic relevance, even from a contemporary point of view, discussing this in detail would go well beyond the scope of the study. The systematic relevance is therefore only discussed in the conclusion ( and occasional footnotes ). Second, Leibniz draws on a variety of terms to describe conscious acts – from ‘apperception’ to ‘conscience’ or ‘consciosité’.4 To
4 The English language differentiates between ‘consciousness’ and ‘conscience’ just as the German language differentiates between ‘Bewusstsein’ and ‘Gewissen’. In French, though, the two fall under one and the same –‘conscience’. The French ‘conscience’ thus equivocates between ‘consciousness’/‘Bewusstsein’ and ‘conscience’/‘Gewissen’. Even though German ( more
describe reflexive acts, he also draws on more than one term – from ‘reflexion’ to ‘actes reflexifs’ or ‘connoissance reflexive’.5 Some of these terms are even ambiguous ( more below ). To prevent confusion, I opted for two rather neutral, general terms in this study. The term ‘awareness’ should point to all sorts of conscious acts ( apperception, conscience, etc.). Meanwhile, ‘reflection’ should point to all sorts of reflexive acts ( reflective knowledge, reasoning, etc.). The notions of awareness and reflection are general enough to not commit us to any specific reading, but they can be qualified so as to be more specific where needed.
§ 1 The problem
I endeavour to show that Leibniz’ s concept of apperception can meaningfully distinguish between awareness, reflection, and animal awareness – that although this concept seems to conflate these three forms of awareness and to complicate matters, it just reflects the fact that awareness is indeed complex. To reach this goal, i. e. to show that Leibniz’ s concept of apperception is not as problematic as it seems, we need to get hold of the problem in the first place. So, what is or seems to be so problematic ? Commentators have repeatedly brought attention to what at least appears to be an inconsistency in Leibniz’ s writings ( Commentators have done so at least since 19th century Germany as we shall see below.). There seems to be an inconsistency when three propositions in Leibniz’ s corpus are held together – what I shall refer to as the ‘classic6 consistency problem’ throughout this study.
precisely Saxon ), Leibniz penned his thoughts mostly in French ( and Latin ), hence working with the term ‘conscience’ ( or ‘conscientia’). It might even seem, prima facie, like he coined the term ‘apperception’ so as to have an equivalent of ‘consciousness’/‘Bewusstsein’ ( more below ). On the evolution of the terminology, see also Thiel (2011, 7 ff.).
5 One might object from the outset that Leibniz did not take much of an interest in the phenomenon of reflection. In his remarks on Descartes’ Principles, for instance, he castigates the Frenchman for having heavily relied on reflection ( urging the reader to rely on sets of symbols and rules instead ) ( GPIV 354 ff. / Remarks on Descartes ). In other writings, though, he praises the power of reflection. In a letter to Tschirnhaus, for instance, he urges the reader to reflect since that does not depend on external circumstances – even a prisoner without a pen and paper could gain knowledge by reflecting ( GMIV 462 / To Tschirnhaus ) ( see also annex 2 ).
6 I call it ‘classic’ since it has been discussed for such a long period of time ( more below ).
§ 1.1 First proposition
The first proposition of the classic consistency problem is that apperception is a kind of reflection. As Leibniz puts it in the Principles :
Ainsi il est bon de faire distinction entre la Perception qui est l’état interieur de la Monade representant les choses externes, et l’ Apperception qui est la Conscience, ou la connoissance reflexive de cet état interieur, laquelle n’ est point donnée à toutes les Ames, ny tousjours à la même Ame. ( GPVI 600 / PNG § 4 )
Thus it is good to distinguish between perception, which is the internal state of the monad representing external things, and apperception, which is consciousness, or the reflective knowledge of this internal state, something not given to all souls, nor at all times to a given soul. ( AG 208 / PNG § 4 )
Leibniz draws here a distinction between perception and apperception ( The basic concepts of Leibniz’ s philosophy such as monad, perception, etc., will be introduced in the first chapter.). Apperception is contrasted with perception – it refers not merely to the internal state of the monad representing external things but to consciousness or reflective knowledge of this state. Leibniz was adamant about distinguishing the two when engaging with the Cartesians.7 For them, we are necessarily aware of what we perceive ; for Leibniz, we are necessarily aware of what we apperceive ( but not of what we perceive ).8 Thus, I might not be aware of the sound of the wind while I sleep even though I still perceive it ( It still has an effect on my sense organs.). I might, however, become aware of the sound of thunder. In such a case, I would have apperceived the thunder.
At first glance, the distinction Leibniz draws between perception and apperception is clear and simple ( as is the way in which he mobilizes the distinction against the Cartesians ). If we take a closer look, though, it will become apparent that it is not so clear and simple after all. Leibniz namely writes that apperception is consciousness or reflective knowledge. This raises a host of questions. Is apperception the same as consciousness and reflective knowledge ? Is apperception either consciousness or reflective knowledge ( the latter being more than just consciousness )? Note also that the term ‘conscience’ in the original French can mean either ( moral ) conscience or consciousness. Is apperception then the same as conscience and reflective knowledge ? Or is it either conscience or reflective knowledge ? Note finally that the clause at the end of the sentence – “something not given to all souls” – obfuscates the meaning of the passage even more. What is it that is not given to all souls ? Is it apperception or
7 The quote continues as follows : “Et c’ est faute de cette distinction, que les Cartesiens ont manqué, en comptant pour rien les perceptions dont on ne s’ apperçoit pas, comme le peuple compte pour rien les corps insensibles.” ( GPVI 600 / PNG § 4 ).
8 On this point, see McRae (1976, 8 ff.).
reflective knowledge ? Provided that the category of souls encompasses both animals and humans ( more in chapter 1), one could also ask if “something not given to all souls” means that this something is given to humans but not animals. But perhaps it is given to “higher” souls ( humans, dolphins, chimpanzees, etc.) but not to “lower” ones ( oysters, etc.)? In fact, there is at least a dozen possible readings of the above-quoted passage from the Principles.9 I shall not go over all these readings here, but I do so in annex 1. Those interested in the finer details of the interpretation of the Principles § 4 should thus consult annex 1.
The first proposition of the classic consistency problem is, hence, that apperception is a kind of reflection. Against the Cartesians’ contention that perception entails awareness, Leibniz differentiates between perception ( which does not necessarily entail awareness ) and apperception ( which does entail it ). In doing so, Leibniz mentions that apperception is consciousness or reflective knowledge. This implies that apperception is closely tied to reflection. It either is a kind of reflection, or it can be of a reflexive kind. The oft-quoted passage from the Principles § 4 is, admittedly, far from transparent. It is worth mentioning, though, that apperception is tied to reflection in the New Essays as well.10 Apperception and reflection are, in any case, very closely related for Leibniz.
§ 1.2 Second proposition
The second proposition of the classic consistency problem is that animals can apperceive. In another famous passage, which commentators refer to as ‘the boar passage’, Leibniz writes that a boar apperceives a person.11
C’ est pourquoy les bestes n’ ont point d’ entendement, au moins dans ce sens, quoyque elles ayent la faculté de s’ appercevoir des impressions plus remarquables et plus distinguées, comme le sanglier s’ apperçoit d’ une personne qui luy crie, et va droit à cette personne [ … ]. ( AVIvi 173 / NE Book II chapter 21 § 5 )
That is why the beasts have no understanding, at least in this sense ; although they have the faculty for awareness [ s’ appercevoir ] of the more conspicuous and outstanding im-
9 I am certainly not the first to have pointed to the equivocal nature of the Principles § 4. See for instance Sticker (1900, 60 ), Gennaro (2003, 360 ), and Jorgensen (2019, 157 ).
10 See AVIvi 53 / NE Preface and AVIvi 139 / NE Book II chapter 9 § 14.
11 Leibniz comments on Locke’ s contention that “the power of perception is that which we call the understanding” ( Essay Book II chapter 21 § 5 ). Leibniz transcribes it as “la puissance d’ appercevoir est ce que nous appellons entendement”. He then rejects the identification, drawing a line between apperceiving and understanding ( the latter being distinct ): “Nous nous appercevons de bien des choses en nous et hors de nous, que nous n’ entendons pas, et nous les entendons, quand nous en avons des idées distinctes [ ].” ( AVIvi 173 / NE Book II chapter 21 § 5 ).
pressions – as when a wild boar is aware [ s’ apperçoit ] of someone who is shouting at it, and goes straight at that person [ ]. ( RB 173 / NE Book II chapter 21 § 5 )
This suggests that at least some animals such as a boar are equipped with the faculty to apperceive. They not only perceive their environment ; they can apperceive it or be aware of it. They can apperceive their surroundings just as the boar apperceives a person shouting at him, etc.
Once again, the quote is not that clear and simple. Leibniz namely makes use of the verb ‘s’ appercevoir’ instead of the noun ‘apperception’.12 This, again, raises questions. Does the verb have the same meaning as the noun ? Or is the noun infused with a technical sense ? Is the appercevoir of the boar passage to be equated with the apperception of the Principles § 4 ?
The second proposition of the classic consistency problem is, hence, that animals can apperceive. The boar passage does not pinpoint exactly what it is that animals can and cannot do. It still shows that animals, for Leibniz, can be aware of their environment. As such, they have a kind of appercevoir at the very least.
§ 1.3 Third proposition
The third proposition of the classic consistency problem is that animals cannot reflect. This Leibniz emphasized over and over again throughout his philosophical career.13 For both epistemic and moral reasons, he argued that animals cannot reflect.14 On the one hand, so the argument goes, we do not see any sign of reflection in animals such as reasoning. On the other hand, they do not have “personality” and cannot carry the moral weight of being a person. We need not
12 ‘Apperception’ results from the nominalization of the French verb ‘apercevoir’ ( or ‘appercevoir’ in 17th century French ). It is interesting to note that the pair ‘apperception’/‘appercevoir’ stands parallel to ‘perception’/‘percevoir’ and that ‘perception’ already performed the double role of nominalizing ‘appercevoir’ ( to notice ) and ‘percevoir’ ( to perceive ). For this reason, one of the proofreaders of the New Essays kept substituting ‘perception’ for ‘apperception’ until he realized that it was no slip of the quill : “Jusqu’ ici, toutes les fois que j’ ai trouvé le mot d’ apperceptions, je l’ ai changé sans scrupule en celui de perceptions. Je juge à present que ce n’ est pas sans dessein que vous avez employé ce terme que j’ ai changé.” ( AVIvi 542 / Notes from Alphonse Des Vignoles ). On these terminological issues, see also Barth (2017, 337– 341).
13 See for instance AVIiv 1583 – 1586 / DM §§ 34 – 35, GPIII 339 / To Lady Masham, and GPVI 600 – 601 / PNG § 5, respectively from 1686, 1704, and 1714.
14 “[ O ]n ne trouve pas que les Bestes fassent des reflexions qui constituent la raison, et donnant la connoissance des verités necessaires ou des sciences, rendent l’ ame capable de personalité. Les bestes distinguent le bien et le mal, ayant de la perception, mais elles ne sont point capables du bien et du mal moral, qui supposent la raison et la conscience.” ( GPIV 492 / Remarks on Foucher )