Thus in Aristotle’s imagination the two worlds, outer and inner, met and came into contact in quite a new way. The mind was, as it were, put at the absolute disposal of matter; it ceased to brood on what arose from within, and turned its attention outwards. The result of this was, of course, an enormous increase in the amount of knowledge concerning the material processes of the outer world. But that was not the first result. For, curiously enough, the first result was a pronounced hardening and sharpening of the mind’s own outlines. Struggling to fit herself, as into a glove, to the processes of cause and effect observed in physical phenomena, the mind became suddenly conscious of her own shape. She was astonished and delighted. She had discovered _logic_. The actual Greek word ‘logic’ (ή λογική τέχνη) is first found with its present meaning in Cicero, but he is speaking of Aristotle; the thing itself and the technique of it was the invention of Aristotle, and it was Aristotle who first used the word _syllogism_ in its modern sense. Perhaps the most significant of all those words which are first found in Aristotle’s treatise on _Logic_ is _analytic_. Here is indeed a new word made to express a new kind of thinking. _Energy_, _entelechy_, _ethics_, _physiology_, and _synonym_, are further examples of words which, as far as we know, were actually created by Aristotle, while we owe _metaphysics_ to the accident of his having treated that subject after (‘meta’) his treatise on _Physics_. _Axiom_, _category_, _mechanics_, _organic_, _physics_, and _synthesis_ are Greek words which take their modern meanings chiefly from Aristotle; but his emphasis on the concrete and his constant gravitation towards a kind of knowledge which might turn out to be practically useful evidently made him a favourite with the Roman mind. Consequently many of his words have come down to us translated into Latin. Among those which we can actually trace are _absolute_, _actual_, _definition_, _equivocal_, _induction_, _instance_, _moral_, _potential_, _property_, _quintessence_, _subject_,[29] _substance_, _virtual_, and the grammatical term _particle_; of the plentiful number which have flown more indirectly from his mind we may mention _conceit_ and _concept_, _deduction_, _difference_, _experiment_, _principle_, and _universal_. In _quantity_ (a translation of the Greek ‘posotes’—‘how-muchness’—and seemingly formed by Aristotle on the analogy of Plato’s ‘poiotēs’, from which we have _quality_) we can perhaps see the beginning of that interest in the _calculable_ aspect of the objects of the visible world from which the exact sciences have arisen. The human mind had now begun to weigh and measure, to examine and compare; and that weighing and measuring has gone on—with intervals—for twenty-three centuries.