On the Possibility of Prognostication
I do not wish to complicate the issue at present by introducing the idea of prognostication or prevision, for I do not understand how anticipation of the future is possible. It is only known to be possible by one of two processes—
(a) Inference—i.e. deduction from a wide knowledge of the present;
(b) Planning—i.e. the carrying out of a prearranged scheme.
And these methods must be pressed to the utmost before admitting any other hypothesis.
As to the possibility of prevision in general, I do not dogmatise, nor have I a theory wherewith to explain every instance; but I keep an open mind and try to collate and contemplate the facts.
Scientific prediction is familiar enough; science is always either historic or prophetic (as Dr. Schuster said at Manchester in the British Association Address for 1915), "and history is only prophecy pursued in the negative direction." This thesis is worth illustrating:—That Eclipses can be calculated forwards or backwards is well known. A tide-calculating machine, again, which is used to churn out tidal detail in advance by turning a handle, could be as easily run backwards and give past tides if they were wanted; but always on the assumption that no catastrophe, no unforeseen contingency, nothing outside the limits of the data, occurs to interfere with the placid course of phenomena. There must be no dredging or harbour bar operations, for instance, if the tide machine is to be depended on. Free-will is not allowed for, in Astronomy or Physics; nor any interference by living agents.
The real truth is that, except for unforeseen contingencies, past, present, and future are welded together in a coherent whole; and to a mind with wider purview, to whom perhaps hardly anything is unforeseen, there may be possibilities of inference to an unsuspected extent. Human character, and action based upon it, may be more trustworthy and uncapricious than is usually supposed; and data depending on humanity may be included in a completer scheme of foreknowledge, without the exercise of any compulsion. "The past," says Bertrand Russell eloquently, "does not change or strive; like Duncan, after life's fitful fever it sleeps well; what was eager and grasping, what was petty and transitory, has faded away; the things that were beautiful and eternal shine out of it like stars in the night." My ignorance will not allow me to attempt to compose a similar or rather a contrasting sentence about the future.