own mind, which is free already, nor very hopeful of freeing that of most people.  The innate ideas were not explicit thoughts but categories employed unwittingly, as people in speaking conform to the grammar of the vernacular without being aware that they do so.  As for extension being the essence of matter, since matter existed and was a substance, it would always have been more than its essence:  a sort of ether the parts of which might move and might have different and calculable dynamic values.  The gist of this definition of matter was to clear the decks for scientific calculation, by removing from nature the moral density and moral magic with which the Socratic philosophy had encumbered it.  Science would be employed in describing the movements of bodies, leaving it for the senses and feelings to appreciate the cross-lights that might be generated in the process.  Though not following the technique of Descartes, the physics of our own day realises his ideal, and traces in nature a mathematical dynamism, perfectly sufficient for exact prevision and mechanical art.

Similarly, in saying that the essence of the soul was to think, Descartes detached consciousness, or actual spirit, from the meshes of all unknown organic or invented mental mechanisms.  It was an immense clarification and liberation in its proper dimension:  but this pure consciousness was not a soul; it was not the animal psyche, or principle of organisation, life, and passion—­a principle which, according to Descartes, was material.  To have called such a material principle the soul would have shocked all Christian conceptions; but if Descartes had abstained from giving that consecrated name to mere consciousness, he need not have been wary of making the latter intermittent and evanescent, as it naturally is.  He was driven to the conclusion that the soul can never stop thinking, by the desire to placate orthodox opinion, and his own Christian sentiments, at the expense of attributing to actual consciousness a substantial independence and a directive physical force which were incongruous with it:  a force and independence perfectly congruous with the Platonic soul, which had been a mythological being, a supernatural spirit or daemon or incubus, incarnate in the natural world, and partly dominating it.  The relations of such a soul to the particular body or bodies which it might weave for itself on earth, to the actions which it performed through such bodies, and to the current of its own thoughts, then became questions for theology, or for a moralistic theory of the universe.  They were questions remote from the preoccupations of the modern mind; yet it was not possible either for Locke or for Descartes to clear their fresh conceptions altogether from those ancient dreams.

What views precisely did Locke oppose to these radical tendencies of Descartes?

In respect to the nature of matter, I have indicated above the position of Locke:  pictorially he accepted an ordinary atomism; scientifically, the physics of Newton.