So far well. Cognition is a very complex network of relatedness involving many terms. What are these terms? For Spencer the internal terms are ultimately nervous (=psychic) shocks in highly integrated aggregates; and the external terms are, proximately at least, things in the environment. But both alike are spoken of as states of consciousness. There is surely an opening for ambiguity here. Sometimes, too, the words subjective affections are used in place of states of consciousness. 'Thus we are brought to the conclusion that what we are conscious of as properties of matter, even down to its weight and resistance, are but subjective affections.'[67] Well, these states of consciousness, these subjective affections, fall into two great classes--the vivid and the faint. The former, which we know as sensations, accompany direct and therefore strong excitations of the nerve-centres; the latter, which we know as remembered sensations, or ideas of sensations, accompany indirect and therefore weak excitations of the same nerve-centres.[68] And then we are told that the aggregate of the faint is what we call the mind, the subject, the _ego_; the aggregate of the vivid is what we call the external world, the object, the _non-ego_.[69] It would seem, then, that the aggregate of vivid _subjective_ affections is the _objective_ world so far as knowable. To say the least of it, this terminology is somewhat perplexing. No doubt our knowledge of the external world involves a subtle and intricate inter-relation of what is experienced vividly and what is experienced faintly--of what is actually presented and what is ideally re-presented. The distinction between them is a valid one. But when Spencer equates this distinction with that between the external world and the mind, as he does in the passages to which I have referred, the validity of his procedure is seriously open to question.