_Argument._--The conscious organism is one that acts. Its consciousness of an external world is not simply the result of the stimuli made by that world on its organs of sense, for it becomes fully aware only of those stimuli which result in deliberated bodily activity. This awareness of an outer world on which it acts is the perception of the organism. Its consciousness is an intensive multiplicity. This multiplicity is arbitrarily dissociated, for convenience’ sake, by the mental organisation, which confers extension and magnitude and succession on those aspects of consciousness which it arbitrarily dissociates from each other. Our notion of space is an intuitive one and depends on our modes of bodily exertion. Our notions of motion and continuity are also intuitive ones, and they cannot be represented intellectually, but we can approximate to them by the methods of the infinitesimal calculus. Mathematical time is only a series of standard events which punctuate our duration. Duration is the accumulated existence and experience of the organism. We cannot prove intellectually that there is a world external to our consciousness, but that this world exists is a conviction intuitively held. CHAPTER II THE ORGANISM AS A MECHANISM 49 _Argument._--If the organism is a physico-chemical mechanism its activities must conform to the two principles of energetics: the law of conservation of energy and matter, and the law of entropy-increase. They conform strictly to the law of conservation. The law of the degradation of energy is true of our experience of inorganic nature, but we can show that it cannot be universally true. Inorganic processes are irreversible ones, and they proceed in one direction only, and in them energy is degraded. Organic processes, that is, the processes carried on in the generalised organism, are irreversible; or, at least, there is a tendency for them to be carried on without necessary dissipation of energy. CHAPTER III THE ACTIVITIES OF THE ORGANISM 83