6 Further recommendable online sites with materials on John Locke are J. Bennett’s collection of early modern texts at http://www.earlymoderntexts.com/, and the Online Library of Liberty at https://oll.libertyfund.org
Notes
* John Locke, An Essay concerning Human Understanding [1690], Bk II, ch. 8, §§ 7–22 inclusive; punctuation, spelling and layout adapted. Several editions are available; the standard critical edition by P. H. Nidditch (Oxford: Clarendon, 1975) preserves the original formatting (pp. 134–43).
1 1 Descartes, Principles of Philosophy [1644], Part IV, article 198.
2 2 Though the date on the title page of the first edition is 1690.
3 3 ‘Animal spirits’: a fine gas or vapour supposed to be the vehicle for the transmission of nerve-impulses.
4 4 Plant extract used in the seventeenth century as a laxative.
5 Substance, Life and Activity: Gottfried Leibniz, New System*
Although Locke (see previous extract) characterized the material world in terms of the ‘primary qualities’ of things, he did make sporadic use of the traditional Aristotelian label ‘substance’, while none the less voicing some reservations about exactly what it meant. If we describe a particle as round and hard, what does it mean to add that it is a substance that is round and hard? ‘If anyone will examine himself concerning his notion of pure substance in general,’ Locke observed, ‘he will find he has no other idea of it at all, but only a supposition of he knows not what support of such qualities which are capable of producing ideas in us.’1
Once this troubling question had been asked, it was not long before some philosophers were suggesting that the notion of substance might be abandoned altogether (see extract 7, below). Others, however, continued to defend the concept of substance as being of the greatest importance. The German philosopher Gottfried Leibniz, a keen supporter of the new mathematical and corpuscular physics that flourished during the latter seventeenth century, came to the conclusion that the notion of substance provided essential metaphysical underpinning for a complete understanding of reality. In his New System, published in French in 1695, Leibniz argues that a purely mathematical account of the world, in terms of extension (size and shape) must be deficient. First, Leibniz insists that we need in our account of reality to recognize the essential unity of things: the world cannot be a mere collection of arbitrary heaps or piles of stuff – ‘an accumulation of parts ad infinitum’; sooner or later we must acknowledge some ultimate units – what Leibniz calls ‘metaphysical atoms’. And second, Leibniz maintains that size and shape alone cannot explain the activity and power found in the universe: ‘extended mass is not of itself enough, and use must also be made of the notion of force which is fully intelligible, although it falls within the sphere of metaphysics’.
Now as we have seen (extract 3 above), Descartes had explained motion by invoking the creative power and continuous conserving action of the supreme substance, God; but Leibniz argues that in favouring this ‘solution’ the supporters of Descartes were simply ‘falling back on a miracle’. Instead, Leibniz offers a metaphysical picture of the world such that activity and energy are involved at the deepest level in the ultimate individual units of being. Reality is composed of an infinite plurality of ‘metaphysical points’ or ‘atoms of substance’ (what Leibniz was later to call ‘monads’). ‘It is only unities which are real and absolutely without parts, which can be the sources of actions, and as it were the ultimate elements into which substantial things can be analysed.’ Leibniz makes it clear that the rational souls of human beings are the most important examples of such individual units of substance, or spontaneous centres of activity (and he thinks this notion underpins our independence and freedom). But even the humblest of bodies are made up of metaphysical units which have something ‘soul-like’ about them: ‘Each simple substance has relations which express all the others, and consequently it is a perpetual living mirror of the universe.’ So, far from the ‘dead’ world of extended matter posited by Descartes, Leibnizian metaphysics presents a universe whose ultimate constituents are in some sense ‘animated’ or ‘alive’, containing within themselves the source of their activity, and internally ordered in such a way as to ensure the harmonious operation of the universe as a whole.
Although I am one of those who have done much work on mathematics, I have constantly meditated on philosophy from my youth up, for it has always seemed to me that in philosophy there was a way of establishing something solid by means of clear proofs. I had travelled far into the world of the Scholastics,2 when mathematics and modern writers3 lured me out again, while still a young man. I was charmed with their beautiful way of explaining nature mechanically, and scorned, with justice, the method of those who only make use of forms or faculties, from which we learn nothing. But later, when I tried to get to the bottom of the actual principles of mechanics in order to give an explanation of the laws of nature which are known through experience, I became aware that the consideration of an extended mass is not of itself enough, and that use must also be made of the notion of force, which is fully intelligible, although it falls within the sphere of metaphysics. It seemed to me also that the opinion of those who transform or degrade the lower animals into mere machines,4 although it seems possible, is improbable, and even against the order of things.
At first, when I had freed myself from the yoke of Aristotle, I had believed in the void and atoms, for it is this which best satisfies the imagination. But returning to this view after much meditation, I perceived that it is impossible to find the principles of a true unity in matter alone, or in what is merely passive, since everything in it is but a collection or accumulation of parts ad infinitum. Now a multiplicity can be real only if it is made up of true unities which come from elsewhere and are altogether different from mathematical points, which are nothing but extremities of the extended and modifications out of which it is certain that nothing continuous could be compounded. Therefore, to find these real unities, I was constrained to have recourse to what might be called a real and animating point or to an atom of substance which must embrace some element of form or of activity in order to make a complete being. It was thus necessary to recall and in a manner to rehabilitate substantial forms, which are so much decried today, but in a way which makes them intelligible and separates the use which must be made of them from their previous abuse. I found then that their nature consists of force and that from this there follows something analogous to feeling and to appetite; and that therefore it was necessary to form a conception of them resembling our ordinary notion of souls. But just as the soul must not be used to explain the detail of the economy of the animal’s body, so I judged in the same way that these forms ought not to be used to explain the particular problems of nature, although they are necessary to establish true general principles. Aristotle calls them first entelechies; I call them, more intelligibly perhaps, primitive forces, which contain not only the act, or the fulfilment of possibility, but also an original activity.
I saw that these forms and these souls must be indivisible like our mind … But this truth revived the great difficulties about the origin and duration of souls and forms. For since every simple substance which possesses a true unity can have its beginning and end by miracle alone, it follows that they could not begin except by creation, nor come to an end except by annihilation. Thus (with the exception of such souls as God still wills to create expressly) I was obliged to recognize that the constitutive forms of substance must have been created with the world and that they go on subsisting always …
Nevertheless I deemed that we ought not to mix without distinction or to confuse with other forms or souls, minds or rational