sensations, through which reasoning becomes possible. Hobbes had evidently fallen in love with algebra as well as with geometry; and it is on the type of algebraic reasoning--in other words, on the type of rigorous deduction--that his logic is constructed. And such a view of the way in which knowledge advances seemed amply justified by the scientific triumphs of his age. But his principle that all motion originates in antecedent motion, although plausible in itself and occasionally revived by ingenious speculators, has not been verified by modern science. Gravitation, cohesion, and chemical affinity have, so far, to be accepted as facts not resoluble into more general facts. Hobbes died before the great discoveries of Newton which first turned away men's minds from the purely mechanical interpretation of energy. That mechanical interpretation led our philosopher to reject Aristotle's notion of sociality as an essentially human characteristic. To him this seemed a mere occult quality, the substitution of a word for an explanation. The counter-view put forth in his great work, _Leviathan_, is commonly called atomistic. But it would be gross flattery to compare the ultimate elements of society, as Hobbes conceived them, to the molecules of modern science, which attract as well as repel each other; or even with the Democritean atoms, which are at least neutral. According to him, the tendency to self-preservation, shared by men with all other beings, takes the form of an insatiable appetite {26} for power, leading each individual to pursue his own aggrandisement at the cost of any loss or suffering to the rest. And he tries to prove the permanence of this impulse by referring to the precautions against robbery taken by householders and travellers. Aristotle had much more justly mentioned the kindnesses shown to travellers as a proof of how widely goodwill is diffused. Our countryman, with all his acuteness, strangely ignores the necessity as a matter of prudence of going armed and locking the door at night, even if the robbers only amounted to one in a thousand of the population. Modern researches have shown that there are very primitive societies where the assumed war of all against each is unknown, predatory conflicts being a mark of more advanced civilisation, and the cause rather than the effect of anti-social impulses.