To us, of course, as beings aware of what we do and achieve, this is simple enough: but it is also true of _things,_ that we only understand them, in so far as we put them in, or invest them with, the same activity and apperception of activity as we are familiar with in our own experience. The veriest materialist cannot help speaking of things as agents, as behaving, as having a function. He would, no doubt, if he were to be cross-examined, refuse to identify himself with the primitive anthropomorphism, or at least zoömorphism of the natural man who sees the river run and the clouds sweep the sky; and he would probably mutter something referring to people who cannot see when they ride a metaphor to death. Still less, perhaps, would he be inclined to adopt the spiritualistic or animistic hypothesis of philosophising physicists, like Fechner, who would accredit even the plants at our feet, and the stars in the sky, with souls, or soul-like centres of their life. But, however he may shrink from what we may call the ontological consequences of his language, there is no doubt that for him the meaning of the world, its reality and truth, is obtained by an interpretation in terms which, rigidly employed, imply their environment by a self-consciousness to which they are relative. Take from him the tacit assumption (which he often finds it difficult to realise just because it is the foundation of all his language) that reality is in the last resort a self-conscious reality, and his words become meaningless, or what he might think worse, metaphorical. To Bacon, who, though not without a strong speculative impulse, approached philosophic dicta from the standpoint of an average intelligent Englishman (and it is on that account that his remarks are often so instructive), it seemed a grave fault of the Stagirite to define the soul, that 'most noble substance,' by words of the second intention. Without substance--a solid something as basis of act and event--the reality of the soul seemed likely to fare badly. Behind consciousness he, like many others, felt there must be a something of which consciousness is the state, act, or predicate and attribute. The thinking must come from a thinker. There must be a permanent subject of thought--a persistent substance which does not disappear when thinking for the nonce stops. And thinking is according to common experience very liable to stops and interruptions. Both Bacon and Locke felt that without this refuge to fall back upon, personal identity was in a bad way, or personality itself little better than a delusion. And therefore when Aristotle, and his modern followers, treated soul and mind as essentially definable by the terms activity, self-realisation, it has been freely urged against them that they are tampering with the pearl of great price which all our hopes and aspirations fondly guard.