128. Ninth. Nothing whose nature is apparent to sense consists of one kind of first beginnings (only).
129. We need not trouble ourselves with his notion of the smallness, smoothness, and roundness of the atoms which make up the mind, qualities which he arrives at from the rapidity with which the mind originates and works out a suggestion, contrasting here the mobility of water with the viscosity of honey. Nor his proof (by the non-diminution of the weight and dimensions of the body at death), that the whole mass of the mind must be exceedingly small. But we may quote, in two of its many forms, his constant reiteration of the unreasonableness of the fear of death, and his philosophic mode of overcoming it:—
‘Some wear themselves to death for the sake of statues and a name. And often to such a degree, through dread of death, does hate of life and of the sight of daylight seize upon mortals, that they consider self-murder with a sorrowing heart, quite forgetting that this fear is the source of their cares (this fear which urges men to every sin), prompts this one to put all shame to rout, another to burst asunder the bonds of friendship; and, in fine, to overturn duty from its very base, since often ere now men have betrayed country and dear parents in seeking to shun the Acherusian quarters. For, even as children are flurried and dread all things in the thick darkness, thus we in the daylight fear at times things not a whit more to be dreaded than what children shudder at in the dark, and fancy sure to be. This terror, therefore, and darkness of mind must be dispelled, not by the rays of the sun and glittering shafts of day, but by the aspect and law of nature.’ Book III. 78.
‘Now no more shall thy house admit thee with glad welcome, nor a most virtuous wife and sweet children run to be the first to snatch kisses, and touch thy heart with silent joy. No more mayest thou be prosperous in thy doings, a safeguard to thine own. One disastrous day has taken from thee, luckless man, in luckless wise, all the many prizes of life. This do men say; but add not thereto: “And now no longer does any craving for these things beset thee withal.” For if they could rightly perceive this in thought, and follow up the thought in words, they would release themselves from great distress and apprehension of mind. Thou, even as now thou art, sunk in the sleep of death, shalt continue so to be in all time to come, freed from all distressing pains; but we, with a sorrow that would not be sated, wept for thee, when close by thou didst turn to an ashen hue on thy appalling funeral pile, and no length of days shall pluck from our hearts our ever-enduring grief. This question, therefore, should be asked of this speaker, what there is in it so passing bitter, if it come in the end to sleep and rest, that any one should pine in never-ending sorrow.’ Book III. 894.
130. To conclude, there is a great deal in Lucretius (whether his own or derived from others does not matter to us) which is of considerable value, even from a modern scientific point of view, though, of course, of far greater value from the point of view of the student of development. But his attempted proofs are for the most part absurd, based, as they generally are, upon mere metaphysical speculations and altogether preposterous analogies.
131. (2.) Boscovich and others endeavoured to dispense with the atom altogether, substituting in its place the conception (which mathematicians often find useful) of a mere geometrical point, which is a centre of force, as it is called. Here we get rid of the idea of substance entirely, but we preserve (all but inertia) those external relations by which alone the atom is capable of making known its presence. Even so great an experimental philosopher as Faraday may be quoted as, to some extent at least, agreeing with this notion. It seems to us, however, that this is the embodiment of an over-refinement of speculation, surrounded on almost all sides by the gravest difficulties. It may suffice merely to mention again the property of mass, or inertia, which Faraday himself seemed to look upon as the one essential characteristic of matter, and which we can hardly bring ourselves to associate with the absence of what we understand by substance.
132. (3.) Another speculation leads us to imagine matter as not ultimately atomic—as, in fact, infinitely divisible. But, if it be so, it must (in order that various elementary physical facts may be capable of explanation) be practically continuous but intensely heterogeneous. That solid or liquid matter has a grained structure of not infinitely small dimensions is proved by many simple and generally known facts; among others by the separation of white light into its constituent colours when refracted through a prism, by the phenomena of capillarity, and by those of contact electricity. If such heterogeneity were only pronounced enough, it appears that the law of gravitation would be capable of accounting for at least the greater number of effects at present attributed to the so-called molecular forces and the force of chemical affinity. Here, however, we are met by the grand difficulty, that of accounting for gravitation. And the only attempt at explanation of gravitation-attraction, which can be called even plausible, can only, with very great straining, be made compatible with this idea of the nature of matter.
133. (4.) The fourth and most recent speculation revives the atom (in the literal sense of the word), but not ‘strong in solid singleness’ like those contemplated by Lucretius,—much rather yielding to the least external force, and thus escaping from the knife or wriggling round it, so that it cannot be cut,—not, however, on account of its hardness, but on account of its mobility, which makes it impossible for the knife to get at it.
This is the vortex-atom theory of Sir W. Thomson, dimly foreshadowed in the writings of Hobbes, Malebranche, and others, but only made distinctly conceivable in very recent times by the hydrokinetic researches of Helmholtz. Helmholtz, in 1858, first successfully attacked the equations of motion of an incompressible frictionless fluid, without introducing the great simplification which had been adopted by his predecessors, and which consisted in supposing the motion to be non-rotational. He proved, among other valuable results, that those portions of the fluid which at any time possess rotation preserve it for ever, and are thus as it were marked off from the others; also that these portions must be arranged in filaments whose direction is at each point the axis of rotation, and that the filaments are either endless, i.e. form closed curves (whether knotted or not), or terminate in the free surface of the fluid.
Hence Sir William Thomson’s idea that what we call matter may consist of the rotating portions of a perfect fluid, which continuously fills space. This definition involves the necessity of a creative act for the production or destruction of the smallest portion of matter, because rotation can only be produced or destroyed by us in a fluid in virtue of its viscosity (or internal friction), and in a perfect fluid there is nothing of the kind.