ONE:We have seen how Greek thought had arrived at a perfectly just conception of the process by which all physical transformations are effected. The whole extended universe is an aggregate of bodies, while each single body is formed by a combination of everlasting elements, and is destroyed by their separation. But if Empedocles was right, if these primary substances were no other than the fire, air, water, and earth of everyday experience, what became of the Heracleitean law, confirmed by common observation, that, so far from remaining unaltered, they were continually passing into one another? To this question the atomic theory gave an answer so conclusive, that, although ignored or contemned by later schools, it was revived with the great revival of science in the sixteenth century, was successfully employed in the explanation of every order of phenomena, and still remains the basis of all physical enquiry. The undulatory theory of light, the law of universal gravitation, and the laws of chemical combination can only be expressed in terms implying the existence of atoms; the laws of gaseous diffusion, and of thermodynamics generally, can only be understood with their help; and the latest develop34ments of chemistry have tended still further to establish their reality, as well as to elucidate their remarkable properties. In the absence of sufficient information, it is difficult to determine by what steps this admirable hypothesis was evolved. Yet, even without external evidence, we may fairly conjecture that, sooner or later, some philosopher, possessed of a high generalising faculty, would infer that if bodies are continually throwing off a flux of infinitesimal particles from their surfaces, they must be similarly subdivided all through; and that if the organs of sense are honeycombed with imperceptible pores, such may also be the universal constitution of matter.26 Now, according to Aristotle, Leucippus, the founder of atomism, did actually use the second of these arguments, and employed it in particular to prove the existence of indivisible solids.27 Other considerations equally obvious suggested themselves from another quarter. If all change was expressible in terms of matter and motion, then gradual change implied interstitial motion, which again involved the necessity of fine pores to serve as channels for the incoming and outgoing molecular streams. Nor, as was supposed, could motion of any kind be conceived without a vacuum, the second great postulate of the atomic theory. Here its advocates directly joined issue with Parmenides. The chief of the Eleatic school had, as we have seen, presented being under the form of a homogeneous sphere, absolutely continuous but limited in extent. Space dissociated from matter was to him, as afterwards to Aristotle, non-existent and impossible. It was, he exclaimed, inconceivable, nonsensical. Unhappily inconceivability is about the worst negative criterion of truth ever yet invented. His challenge was now35 taken up by the Atomists, who boldly affirmed that if non-being meant empty space, it was just as conceivable and just as necessary as being. A further stimulus may have been received from the Pythagorean school, whose doctrines had, just at this time, been systematised and committed to writing by Philolaus, its most eminent disciple. The hard saying that all things were made out of number might be explained and confirmed if the integers were interpreted as material atoms.
FORE:The qualities which enabled Epicurus to compete successfully with much greater thinkers than himself as the founder of a lasting sect, were practical rather than theoretical. Others before him had taught that happiness was the end of life; none, like him, had cultivated the art of happiness, and pointed out the fittest methods for attaining it. The idea of such an art was a real and important addition to the resources of civilisation. No mistake is greater than to suppose that pleasure is lost by being made an object of pursuit. To single out the most agreeable course among many alternatives, and, when once found, steadily to pursue it, is an aptitude like any other, and is capable of being brought to a high degree of perfection by assiduous attention and self-discipline.211 No doubt the capacity for enjoyment117 is impaired by excessive self-consciousness, but the same is true of every other accomplishment during the earlier stages of its acquisition. It is only the beginner who is troubled by taking too much thought about his own proficiency; when practice has become a second nature, the professor of hedonism reaps his harvest of delight without wasting a thought on his own efforts, or allowing the phantom of pleasure in the abstract to allure him away from its particular and present realisation. And, granting that happiness as such can be made an object of cultivation, Epicurus was perfectly right in teaching that the removal of pain is its most essential condition, faulty as was (from a speculative point of view) his confusion of the condition with the thing itself. If the professed pleasure-seekers of modern society often fail in the business of their lives, it is from neglecting this salutary principle, especially where it takes the form of attention to the requirements of health. In assigning a high importance to friendship, he was equally well inspired. Congenial society is not only the most satisfying of enjoyments in itself, but also that which can be most easily combined with every other enjoyment. It is also true, although a truth felt rather than perceived by our philosopher, that speculative agreement, especially when speculation takes the form of dissent from received opinions, greatly increases the affection of friends for one another. And as theology is the subject on which unforced agreement seems most difficult, to eliminate its influence altogether was a valuable though purely negative contribution to unanimity of thought and feeling in the hedonistic sect.In multiplying the variations of a measuring implement by mechanism, it is obvious that movable joints must be employed; it is also obvious that no positive joint, whether cylindrical or flat, could be so accurately fitted as to transmit such slight movement as occurs in gauging or measuring. This difficulty is in most measuring instruments overcome by employing a principle not before alluded to, but common in many machines, that of elastic [151] compensation.
FORE:After I had been incarcerated for about two hours I was taken to the commanding officer, Major Krittel, or rather to one of his subordinates, Captain Spuer, who was having a violent altercation with his chief. The captain appeared to insist with great force that the whole place should be burned down and all the prisoners shot. But the major seemed to be a tolerably reasonable man, tried to soothe the captain, and at last put down his foot, saying that he had had enough. The captain, a rude, fat fellow, sat down at a desk and bellowed at me:
