BRIEF CRITIQUE OF " PSYCHO-PHYSICAL PARALLELISM ". 377 of what takes place when states of consciousness that are pre- dominatingly states of feeling and conation, and states that are perceptions of conditions or changes of the bodily organism, follow each other in reciprocal dependence. Take out of the stream of consciousness, out of the experienced life of the soul, the red- blood of felt-strivings, of successful or inhibited willing, of pain and pleasure following upon observed changes in superficial or more interior parts of the body, and the empirical data for all our meta- physical conceptions would be gone. There would no longer be any demand upon psychology to interpret the "stream of con- sciousness," with its unity in duality, in terms of ontological consciousness. When, then, either physicists or psychologists, or both acting in conjunction, deny the validity of the ontological interpretation of the psychological facts, they are passing quite beyond the limits of the working hypothesis which is alone legiti- mate for both kinds of work. They should both be called sharply to account for the transgression at the final court of appeal, which is philosophy. And I have little hesitation in affirming that, so far as my acquaintance with the subject goes, not one of the modern advocates of the hypothesis of psycho-physical paral- lelism has ever given evidence of having bestowed the needed criticism upon the categories which the statement of the hypothesis necessarily involves. What is it to be, in reality, a cause ? What do we mean by actual causal relations or connexions ? What is it really to be, as all things and minds are ; and what to be related as every individual man's body certainly seems to be reciprocally related to that same individual's mind ? 6. But to return to the empirical point of view. From this point of view, and judged impartially by the evidence which ap- pears from this point of view, the hypothesis of psycho-physical parallelism is most unscientific. It is, indeed, either unintelligible, or inadequate, or plainly false. With regard to some of the in- definitely numerous and complex relations which do actually reveal themselves to science as maintained between the phenomena as- cribed to the Ego as their subject and the phenomena ascribed to the physical organism as their subject, it has all of these defects as a hypothesis. How, briefly stated, shall we clearly understand the figure of speech embodied in the word "parallelism " ? Plainly not in the geometrical or spatial meaning. Nor can it be strictly interpreted in terms of a temporal or time series. So far as ex- perience shows, what we have is interdependent sequences, with impressive dynamic accompaniments, between these two classes of phenomena. But such an experience is the very one on which we build up our theories of reciprocal causation. Moreover, the time- series of psychoses differs from the time-series of neuroses so far as we know anything about the latter in several important ways. And there are few of the reigning fallacies of psychology more mis- taken than that which has embodied itself in the comparison of the life of the mind in time to a continuously flowing " stream ". Still
