Letters on Reasoning

Abstract

THIS book is in the form of letters addressed to the author's children, and is lucidly and fluently written. Mr. Robertson's counsels upon the duty and importance of clear thought and scrupulous candour in reasoning are excellent, and it is to be hoped the children to whom the letters are addressed will profit by them. It is a pity Mr. Robertson does not always follow his own good advice. In the constant polemic against theism, to which he recurs in chapter after chapter, he often unconsciously misrepresents the case against which he is arguing, and his own reasoning is not unfrequently vicious. Thus it is hardly fair to the advocates even of the crudest form of the “design” hypothesis to meet Paley's argument about the traveller who finds the watch in the desert with the retort that the argument assumes the desert at least to be “undesigned.” All that is assumed is that the desert, whether “designed” or not, does not, like the watch, exhibit design of a specific kind recognisable by the traveller. And Mr. Robertson's own chief argument against theistic design, that an infinite series, such as the “totality of events,” cannot have any specific predicates beyond the one predicate of “infinity,” is surely very doubtful. If I can make predications about the infinite series of the natural numbers (such as, e.g., that every member of it has a next term, that every member is commensurable with every other), why not of the infinite series of “events?” Similarly, the argument used in discussing psychological determinism, that no one predicate, such as, e.g., “free,” can be applied to all volitions, since they are an infinite series belonging to no wider species, is really fallacious. For in psychology the very need of a precise definition of a volition compels us to distinguish volitions from other psychical states, such as impulses, cravings, resolutions, and volitions thus come to be an infinite series, no doubt, but an infinite series of which the law of formation is known. The infinity of such a series in no way excludes specific predication about it. Mr. Robertson presumably thinks that the “totality of events” is a series of which we do not know the formative law. But this is just what he has to prove against the theist. He is not entitled to assume the point at issue as if it were a self-evident axiom of thought.

Letters on Reasoning.

By J. M. Robertson. Pp. xxviii + 248. (London: Watts and Co., 1902.)