THE CONSTITUTION OF THOUGHT. 493 of which the systematic thinker reflects doubt upon his whole process : and he begins again with some other way of as- signing the initial differentiae. Thus gradually drawing in our circlings and hoverings more to its own lines, the " world " as we name the gradually evident system becomes to us more and more simply trustworthy. The directions of its significances are assured to us through the assigning (under persistent regulation by the pressure of the presentative order) of conditions through Thought. The question of cause is here seen rising, as I suspect it does rise, in the cleft between cases of succession which are so far similar as to antecedents that similar expectations are generated, but which diverge in their issues. If the perti- nent question is disguised in the outwardly absolute and discontinuous form, " What is the cause of this class of pheno- mena ? and of this ? and of this ? " its substance is more truly expressed in the forms ever modestly limited by the contrasts of experience " Why is it that A, so often followed by B, is not now followed by it ? " or " Why should A be followed by B at other times rather than now ?" 1 For who practically makes of the human intellect scientific or other the extravagant demand that it should face the sheer stu- pendous task of collecting the group of antecedents widen- ing out into a guard of essential favouring conditions lying about us in every direction to the depth of a radius of a whole universe for aught we can know on which an event will invariably and unconditionally follow? From day to day, from century to century, our movement is to go on defining the special phenomenal conditions of any class of events just so far (we can reach no farther), and in such ways, as the variations of our situations, accidental or pur- posely induced, have enabled us to define them. And it were hard if knowledge might not thus begin to be science, and progressively deeper science though without the slightest prospect that it should ever be entirely complete de profundis in respect of one single instance of causation. 1 Radium has attracted immense curiosity through the hitherto cus- tomary fulfilment of those relatively commonplace expectations with which it startlingly conflicts. And is the attempt to formulate a reason for the attendance of remarkable phenomena of radio-activity upon certain presentations made outside and beyond the measure of that contrast which they and other objects mutually afford ? 33
