Leibniz’s New Essays on Human Understanding
Gottfried Wilhelm Leibniz (1646–1716) wrote the New Essays on Human Understanding (or ‘Nouveaux essais sur l’entendement humain’, as it was originally called in French) as an extended commentary on Locke’s Essay Concerning Human Understanding. It was finished in 1704, and is one of only two long-form works that Leibniz completed (the other being his Theodicy of 1710). However, Locke died shortly after Leibniz completed the work and he is reported to have decided against publishing a critical work on Locke so soon after his death. Leibniz thus put the manuscript away and it would not end up being published until long after Leibniz had died, in 1765.
Though originally written as a philosophical treatise, Leibniz converted the book to dialogue form in order to make it more reader-friendly. This was probably a mistake, as it mostly seems to have resulted in an awkward and clunky presentation of Locke’s and Leibniz’s views, rather than the more elegant prose for which Leibniz is known. But, despite the awkwardness of its presentation, it is an important work, both as a statement of Leibniz’s views, and as a sophisticated and sustained rationalist treatment of the nature of the mind.
The dialogue takes place between two figures: Philalethes (‘lover of truth’ – who broadly represents Locke) and Theophilus (‘lover of God’ – who broadly represents Leibniz).
On Innate Ideas
In the opening pages of the New Essays Leibniz explicitly aligns his philosophical views with those of Plato and against what he takes to be the Aristotelian empiricism of Locke. He says,
although the author of the Essay says a thousand fine things of which I approve, our systems are very different. His bears more relation to Aristotle’s and mine to Plato’s, although we both differ in many ways from the doctrines of these two ancients. He is more popular while I am forced at times to be a little more esoteric and abstract, which is not an advantage to me, especially when writing in a living language. (NE Preface, 291) 1
The Dispositional Account of Ideas
Leibniz breifly describes some problems with Locke’s position that all ideas are conscious as follows.
Our able author seems to claim that there is nothing potential (virtuell) in us, and even nothing that we are not always actually conscious of perceiving (appercevions). But he cannot hold this in all strictness; otherwise his position would be too paradoxical, since, again, acquired habits and the contents of our memory are not always consciously perceived (apperfues) and do not even always come to our aid when needed, though often we easily recall them to mind when some trivial occasion reminds us of them, as when we need only the beginning of a song to make us remember the rest. (NE Preface,
Leibniz is here trying to avoid one of the central criticisms Locke levies at the strong version of Nativism—viz., that if we are not always aware of supposedly innate ideas or principles, as children and the various other kinds of people Locke lists presumably are not, then that means we do not have any innate ideas.
What Leibniz points out is that there are many ideas that a subject might be said to ‘have’ in the sense that the subject has the disposition to think using them (e.g. if I tell you that an elephant makes a poor typist you come to have a thought that you presumably weren’t entertaining a moment ago, but nevertheless had the disposition to do so).
Recall that Locke argued against two versions of the nativist view. According to the strong version all children would have knowledge of metaphysical and logical truths. Locke thinks this is clearly empirically false. According to the weak version, ideas and principles are innate in the sense that through the use of reason, mature and rational people would come to assent to the content of the ideas or principles. But Locke thinks this is either false (because it would make derivative knowledge innate) or trivial (because it would make all knowledge innate).
Locke puts the triviality thesis this way,
it is observable, that this saying, that men know and assent to these maxims “when they come to the use of reason,” amounts in reality of fact to no more but this,—that they are never known nor taken notice of before the use of reason, but may possibly be assented to some time after, during a man’s life; but when is uncertain. And so may all other knowable truths, as well as these; which therefore have no advantage nor distinction from others by this note of being known when we come to the use of reason; nor are thereby proved to be innate, but quite the contrary. (ECHU I.i.13)
We saw that Descartes has his own reply to the argument Locke levies at strong Nativism based on the claim that prior to adulthood the mind is too immersed in the sensory experience of the body to adequately reflect on the innate ideas it possesses. But the triviality challenge that Locke raises is perhaps more difficult to answer. Leibniz takes up this challenge. As he says in the NE,
PHIL: But suppose that truths can be imprinted on the understanding without being perceived by it: I don’t see how they can differ, so far as their origin is concerned, from ones that the understanding is merely capable of coming to know.
THEO: The mind is capable not merely of knowing them, but also of finding them within itself. If all it had was the mere capacity to receive those items of knowledge – a passive power to do so, as indeterminate as the power of wax to receive shapes or of a blank page to receive words – it would not be the source of necessary truths, as I have just shown that it is. For it cannot be denied that the senses are inadequate to show their necessity, and that therefore the mind has a disposition (as much active as passive) to draw them from its own depths…(NE I.i.79-80)
So the challenge that Leibniz takes up from Locke is to show how the innateness of at least some ideas is compatible with (i) their being dispositions, and thus of our not always being aware of them (as with children) and (ii) the trivial claim that the mind has a capacity to understand things that are presented to it.
Leibniz tries to illustrate the non-trivial sense in which he thinks innate ideas are dispositional by appeal to an analogy.
if the soul were like these empty tablets, truths would be in us as the shape of Hercules is in a block of marble, when the marble is completely indifferent to receiving this shape or another. But if the stone had veins which marked out the shape of Hercules rather than other shapes, then that block would be more determined with respect to that shape and Hercules would be as though innate in it in some sense, even though some labor would be required for these veins to be exposed and polished into clarity by the removal of everything that prevents them from appearing. This is how ideas and truths are innate in us, as natural inclinations, dispositions, habits, or potentialities [virtualites] are, and not as actions are, although these potentialities are always accompanied by some corresponding, though often insensible, actions. (NE Preface, 294)
There is a sense in which the figure of Hercules is ‘in’ the second block of marble in a way in which it is not ‘in’ the first block. According to Leibniz, the second, veined block would be more ‘inclined’ or disposed to take on the shape of Hercules. So the claim is not that the mind is simply a passive capacity to understand what it is presented with, but rather that it has an inclination or propensity—a disposition—to understand certain kinds of things and in particular ways. This in itself doesn’t show that the dispositions possessed by the mind are reliable guides to how things are (i.e. that the ideas are true). Something more would need to be said for that conclusion. But Leibniz’s point is perhaps enough to avoid the worry of triviality.
On Leibniz’s view, the basic principles of logic, mathematics, and metaphysics are all principles which work with the grain of the mind (to stay with the marble analogy). They are thus dispositionally innate, and not derived from experience.
In addition to Leibniz’s claim that our innate knowledge is dispositional (or that the ideas which constitute this knowledge are dispositional), Leibniz also argues that we have inexplicit or ‘potential’ knowledge.
we use these maxims without having them explicitly in mind. It is rather like the way in which one has implicitly in mind the suppressed premises in enthymemes, which are omitted in our thinking of the argument as well as in our outward expression of it. (I.i.76)
Leibniz argues that, for example, ‘all the propositions of arithmetic and geometry should be regarded as innate’ (I.i.77). Exactly what he means by this is not altogether clear. It would seem to invite just the kinds of empirical objections that Locke raises in his Essay. The appeal to enthymemes suggests one possible interpretation of Leibniz’s argument. An enthymeme is an argument with a missing, implicit, or ‘suppressed’ premise. For example, the inference that ‘Locke is mortal because he is human’ is enthymematic. It fails to make explicit the premise that all humans are mortal. Once that premise is made explicit the inference is valid. Presumably, any person who made the former inference would also be prepared to make the latter, in which the missing premise is made explicit.
Leibniz might be thinking that something similar is true of innate ideas. One is said to have them enthymematically in the sense that, when challenged one would be able to supply the missing premise employing the supposedly innate idea in an argument.
In the end, though, it isn’t really clear that this strategy is sound. The claim that certain mathematical truths follow logically from others in no way guarantees that if someone is certain that 2 + 2 = 4 is true, that they have come to that truth by means of a manipulation of logical rules (as Leibniz believes) (cf. @wilson1967, 359). Worse, it isn’t clear how we could attribute such ‘potential’ knowledge to children, who seem unable to explain the abstract principles that justify their certainty in particular truths such as the principle of non-contradiction and the denial of some particular contradiction. The child simply cannot articulate the general principle when challenged. So Leibniz’s appeal to enthymemes isn’t obviously plausible, at least as a general explanation of the ‘potential’ way in which innate ideas are known.
Reflection and Innateness
In response to the Lockean view that we gain many ideas via reflection Leibniz makes the following puzzling claim:
Perhaps our able author will not entirely disagree with my opinion. For after having devoted his whole first book to rejecting innate illumination, understood in a certain way, he admits, however, at the beginning of the second book and in what follows, that the ideas which do not originate in sensation come from reflection. Now, reflection is nothing other than attention to what is within us, and the senses do not give us what we already bring with us. Given this, can anyone deny that there is a great deal innate in our mind, since we are innate to ourselves, so to speak, and since we have within ourselves being, unity, substance, duration, change, action, perception, pleasure, and a thousand other objects of our intellectual ideas? And since these objects are immediate and always present to our understanding (though they may not always be perceived consciously on account of our distractions and our needs), why should it be surprising that we say that these ideas, and everything that depends upon them, are innate in us? (NE Preface, 294)
Leibniz’s claim seems to be that it is in virtue of ‘reflection’ on one’s own nature that one comes to have the innate ideas characteristic of metaphysics and logic (e.g. /being, unity, change, identity, etc./). Is such reflection supposed to be equivalent to innateness?
Remember that, for Locke, reflection is characterized by an awareness of the mind’s operations. As he puts it
the operations of our own minds within, as the objects of reflection, are to me the only originals from whence all our ideas take their beginnings. The term operations here I use in a large sense, as comprehending not barely the actions of the mind about its ideas, but some sort of passions arising sometimes from them, such as is the satisfaction or uneasiness arising from any thought. (ECHU II.i.4)
Locke, interestingly, seems to take the kinds of activity (or ‘operation’) of which the mind is capable as being themselves innate. There are certain things that minds can do simply in virtue of being minds. What Locke denies is that the mind has any material upon which to work prior to experience.
Is there a substantive disagreement here between Locke and Leibniz? One manner in which there appears to be disagreement concerns the “reach”, as it were, of reflection. For example, in a note during Leibniz’s study of Locke’s Essay Leibniz claims,
It is very true that our perceptions of ideas come either from the external senses or from the internal sense, which one may call reflection; but this reflection does not limit itself solely to the operations of the mind [esprit], as is said [in Locke’s ECHU II.i.4]; it extends to the mind itself, and it is in apperceiving [s’appercevant] it that we apperceive [appercevons] substance [@leibniz1978-v5, 23-4].
Leibniz repeats something like this view in later work.
it is the knowledge of necessary and eternal truths which distinguishes us from simple animals and gives us reason and the sciences, lifting us to the knowledge of ourselves and of God…it is thus, as we think of ourselves, that we think of being, of substance, of the simple and the compound, of the immaterial, and of God himself, conceiving of that which is limited in us as being without limits in him. These reflective acts provide us with the principal objects of our reasonings [@leibniz1969a, 645-6, §§29-30].
The question is how to evaluate these claims. Is Leibniz making a phenomenological claim about the nature of conscious awareness of oneself? Or some other sort of claim? If it is something else then what is it?
Leibniz’s Reasons for Denying the ‘Blank Slate’ Claim
According to Locke’s positive conception of the mind, the mind is a ‘tabula rasa’ or blank slate, which derives all of its knowledge from experience. Experience consists of two sources—sensation, or ideas from external things—and reflection, or ideas gained from introspecting on the activity of the mind.
One reason why Leibniz must reject Locke’s position is because Leibniz holds the following three positions:
- There is no genuine causal interaction between minds and bodies
- Minds cannot be qualitatively identical (because blank) but numerically distinct at birth/creation
- Sense experience can never give us knowledge of necessary truths, but only of contingent matters of fact
Parallellism requires that we cannot explain how experience could cause the mind to have an idea with a particular content concerning the world, since there is no causal interaction between the world and one’s mind.
Experience is necessary, I admit, if the soul is to be made to have such and such thoughts, and if it is to take heed of the ideas that are in us. But how could experience and the senses provide the ideas? Does the soul have windows? Is it similar to writing-tablets, or like wax? Clearly, those who take this view of the soul are treating it as fundamentally corporeal. (NE II.i.110)
Concerning individuation, if one holds, as Leibniz does, to the identity of indiscernables, then how does an empiricist individuate two minds prior to having any experience? If the mind is just a blank slate then there can be no qualitative difference between one mind and another prior to any experience. But then the plurality of minds seems inexplicable? How could one mind become many?
Finally, Leibniz says the following in support of the Necessity claim:
Although the senses are necessary for all our actual knowledge, they are not sufficient to give us all of it, since the senses never give us anything but instances, that is, particular or individual truths. Now all the instances confirming a general truth, however numerous they may be, are not sufficient to establish the universal necessity of that same truth, for it does not follow that what has happened before will always happen in the same way. (NE Preface, 292)
This is perhaps the strongest argument of Leibniz’s against Locke’s empiricism and in favor of some version of Nativism. One version of this argument (or at least related to it) typically goes under the moniker of the ‘poverty of the stimulus’, and has been used to great effect in arguments for the innateness of our knowledge of grammatical rules necessary for speaking a language competently.
There is still an important question here regarding how the understanding or intellect itself furnishes the subject with knowledge of necessity, but experience (or at least sensation) seems to provide no basis for such knowledge.
References & Further Reading2
Here I cite the New Essays by book/chapter/page number in the Ariew & Garber version (Preface) and by book/chapter/margin page in the excerpts from the Bennet version (e.g. I.i.79-80). Citation of Locke’s Essay (ECHU) will be by book/chapter/paragraph. ↩︎
[@bennett2001a; @garber2011; @gennaro1999a; @jolley1986; @jolley1990; @jolley1995a; @look2013; @mcrae1976] ↩︎