It is naturally not conceivable that by a mere caprice of nature the validity of the principles discovered should be limited exclusively to the character of the material in which they were obtained—i.e., to series of nonsense syllables. They may be assumed to hold in an analogous way for every kind of idea-series and for the parts of any such series. It goes without saying, wherever relations exist between the separate ideas, other than those of temporal sequence and separation by intermediate members, these forces will control the associative flow, not exclusively, but with reference to all the modifications and complications introduced by relations of various affinities, connection, meaning, and the like.
At any rate, it will not be denied that the doctrine of Association would gain through a general validity of these results a genuine rounding out and, so to say, a greater reasonableness. The customary formulation, “ideas become associated if they are experienced simultaneously or in immediate succession,” has something irrational about it. If the immediacy of succession is taken precisely, the principle contradicts the most common experiences. If it is not taken exactly, then it is hard to state what kind of sequence is properly meant At the same time it is not clear why a sequence not quite direct should have an advantage which suddenly disappears in the case of a sequence still more indirect. As we now know, the directness or indirectness of the sequence is without effect upon the general nature of what happens between ideas which succeed each other. In both cases connections are formed which on account of their complete similarity can be designated only by the common term, Association. But these are of different strength. As the succession of united ideas approaches ideal immediacy the connecting threads grow stronger, and in proportion as it departs from this ideal, these threads grow weaker. The associations between more distant terms, although actually present and demonstrable under proper conditions have, nevertheless, on account of their slight strength, practically no significance. The associations between adjacent terms are, on the contrary, of relatively great importance, and will make their influence abundantly felt. Of course, if the series were left entirely to themselves and if they were always produced in precisely the same order, for each term there would appear only one association, the relatively
