(p.172) Appendix I Atomism
(p.172) Appendix I Atomism
(p.172) Appendix I
A classical ‘scientific’ statement of atomism—or, more precisely, a statement of atomism by someone who was, among other things, a physicist of the highest eminence—is that of Newton, who in Query 31 of his Optics, famously writes:
All these things being considered, it seems probable to me, that God in the beginning formed Matter in solid, massy, hard, impenetrable, moveable particles, of such sizes and figures, and with such other properties, and in such proportion to space, as most conduced to the end for which he formed them; and that these primitive particles, being solids, are incomparably harder than any porous bodies compounded of them; even so very hard, as never to wear or break in pieces; no ordinary power being able to divide what God himself made one in the first creation. While the particles continue entire, they may compose bodies of one and the same nature and texture in all ages: But should they wear away, or break in pieces, the nature of things depending on them would be changed. Water and earth, composed of old worn particles and fragments of particles would not be of the same nature and texture now, with water and earth composed of entire particles in the beginning. And therefore, that nature may be lasting, the changes of corporeal things are to be placed only in the various separations and new associations and motions of these permanent particles.1
By way of contrast, a telling commentary on atomism cloaked in the garb of physical theory is that of Kant, in a passage from the Critique of Pure Reason, a passage expressing a philosophical perspective to which I find myself largely sympathetic. Kant here calls into question unreflective yet a prioristic tendencies towards atomism which have arisen—most ironically, perhaps—within science itself, and which, though they have been displaced by scientific progress since Kant's day, appear still to linger on in images of science within the popular imagination and philosophy. He writes:
Almost all natural philosophers, observing… a great difference in the quantity of various kinds of matter in bodies that have the same volume, unanimously conclude that this volume… must in all material bodies be empty in varying degrees. Who would have ever dreamt of believing that these students of nature… would base such an inference solely on a metaphysical presupposition—the sort of assumption they so stoutly profess to avoid? They assume that the real in space (I may not name it impenetrability or weight, since these are empirical concepts) is everywhere uniform and varies only in extensive magnitude, that is, in amount. Now to this presupposition, (p.173) for which they could find no support in experience, and which is therefore purely metaphysical, I oppose a transcendental proof, which does not indeed explain the difference in the filling of spaces, but completely destroys the supposed necessity of the above presupposition, that the difference is only to be explained on the assumption of empty space. My proof at least has the merit of freeing the understanding, so that it is at liberty to think this difference in some other manner, should it be found that some other hypothesis is required for the explanation of the natural appearances. For we then recognize that although two equal spaces can be completely filled with different kinds of matter, so that there is no point in either where matter is not present, nevertheless every reality has, while keeping its quality unchanged, some specific degree (of resistance or weight) which can, without diminution of its extensive magnitude or amount, become smaller and smaller in infinitum, before it… vanishes out of existence. Thus a radiation which fills space… can diminish in its degree in infinitum, without leaving the smallest part of this space in the least empty. It may fill the space just as completely with these smaller degrees as another appearance does with greater degrees. I do not at all intend to assert that this is what actually occurs… but only to establish from a principle of pure understanding that the nature of our perceptions allow of such a mode of explanation.2
Kant here focuses on spontaneous tendencies towards the reduction of notions associated with measuring and continuity to notions involving counting and discreteness, taking issue with the view that space‐filling stuff of varying degrees of density must be conceived in terms of varying numbers of uniformly solid atoms and the void. But, contrary to the unselfconscious ‘scientific atomists’, Kant says nothing as to how the world must be—only as to how it might be, and in this way, as he forcefully remarks, the understanding is freed from a straightjacket in which it is liable to bind itself. And just this, as it seems to me, is the liberating potential of enquiry into the distinctive content of terms or concepts designating stuff.
If he rejects atomism, Kant also appears to reject its generalized counterpart, the world‐of‐bodies view. In his Posthumous Works, in particular, Kant advocates a conception of what M. Norton White characterizes as ‘a primordial ether filling space as a continuum’. Kant writes:
The elementary system of the moving forces of matter depends upon the existence of a substance which is the basis (the primordially originating moving force) of all moving forces of matter, and of which it can be said as a postulate (not as an hypothesis): There exists a universally distributed all‐penetrating matter within the space it occupies or fills through repulsion, which agitates itself uniformly in all its parts and endlessly persists in this motion.3
(p.174) In any case, within natural science times have really changed; while an atomistic image of the doctrines of natural science, and so of the world that it depicts, clearly lingers on within philosophy, physics has itself moved dramatically forward. The rigid atomism of the period from Newton to the early twentieth century found itself obliged to give way to an openness to many rather strange and novel concepts—sometimes harking back to those of early Greece. For example, in a special Scientific American report entitled ‘Brave New Cosmos’ (February 2001), we are told that over the past several years
observations have convinced cosmologists that the chemical elements and the dark matter combined amount to less than half the content of the universe. The bulk is a ubiquitous ‘dark energy’ with a strange and remarkable feature: its gravity does not attract. It repels. [It is] known as quintessence… an allusion to ancient Greek philosophy, which suggested that the universe is composed of earth, air, fire and water plus an ephemeral substance… The dynamism is what cosmologists find so appealing about quintessence. The biggest challenge for any theory of dark energy is to explain the inferred amount of the stuff.…
(1) I. Newton, Optics, or, a Treatise of the Reflections, Refractions, Inflections and Colours of Light, 4th edn. (London, 1730).
(2) I. Kant, Critique of Pure Reason, 206–7; italics mine. It is striking that, while later in this passage Kant speaks of various kinds of matter as filling space or spaces, his initial remarks, in which he speaks of ‘various kinds of matter in bodies that have the same volume’, suggest a conception whereby the existence of matter is confined to the constitution of discrete objects.
(3) Kant's Gesammelte Schriften, ed. Preussischen Akademie der Wissenschaften, vols. 21–2, Opus postumum (Berlin and Leipzig, 1936), 21: 593; quoted by M. Norton Wise in Conceptions of Ether: Studies in the History of Ether Theories, 1740–1900, ed. G. N. Cantor and M. J. S. Hodge (Cambridge: Cambridge University Press, 1981). I must thank my colleague Professor Tian Yu Cao of Boston University for kindly drawing this reference to my attention.