When, on the other hand, the causal factor is not known but only inferred with greater or less probability, the justification of the postulation of a subconscious process may be invalidated by the uncertainty of the inference. If for example a person raises his right hand or has a number come into his head without obvious cause, any _inferred_ antecedent experience as the causal factor must be open to more or less doubt, and, therefore, a subconscious process cannot be postulated with certainty. This uncertainty seriously affects the validity of conclusions drawn from clinical phenomena where the antecedent experience as well as a subconscious process must be inferred and perhaps even a matter of guesswork. Let us examine then, a few selected phenomena where the causal factor in the process is a known antecedent conscious experience, one which can be logically related to the succeeding phenomenon only by the postulation of an intervening process of some kind. By an analysis of the antecedent experience and the caused phenomenon into their constituent elements we shall often be able to infer the functional characteristics of this intervening process. Then, if the subject is a favorable one, by the use of hypnotic and other methods we may be able to obtain an insight into the intrinsic nature of the subconscious process and determine how far it is conscious and how far unconscious. Necessarily the most available phenomena are those experimentally induced. We can arrange beforehand the causal experience and the phenomenon which it is to determine—an hallucination, a motor automatism, a dream, a conscious process of thought, or the product of an intellectual operation. The number of observations we shall examine might be made much larger and the types more varied. Those I have selected have such close analogies with certain experiences of everyday and pathological life that what is found to be true of them will afford valuable fundamentals in the elucidation of these latter experiences.[80] =Subconscious processes in which the causal factor was antecedently known.=—I. The evidential value of _post-hypnotic phenomena_ ranks perhaps in the first place for our purpose as the conditions under which they occur are largely under control. Among these showing subconscious processes of a high order of intelligence are: (a) The well-known subconscious mathematical calculations which I cited in a previous lecture (p. 96). There is no possible explanation of this phenomenon except that the calculation was a subconscious process and done either coconsciously or unconsciously. That it may be done, in some cases, by coconscious processes of which the subject is unaware is substantiated by the evidence.[81] In other cases this does not appear to be wholly the case if we can rely upon hypnotic memories. We will examine this process in connection with: