process of learning by heart is completed. For if the process of learning by heart is sometimes carried past that moment and sometimes broken off before it, then part of the differences found under the varying circumstances would be due to this inequality, and it would be incorrect to attribute it solely to inner differences in the series of ideas. Consequently among the different reproductions of, say, a poem, occurring during the process of its memorisation, the experimenter must single out one as especially characteristic, and be able to find it again with practical accuracy.
In the second place the presupposition must be allowed that the number of repetitions by means of which, the other conditions being unchanged, this characteristic reproduction is brought about would be every time the same. For if this number, under conditions otherwise equivalent, is now this and now that, the differences arising from varied conditions lose, of course, all significance for the critical evaluation of those varying conditions.
Now, as far as the first condition is concerned, it is easily fulfilled wherever you have what may properly be called learning by heart, as in the case of poems, series of words, tone-sequences, and the like. Here, in general, as the number of repetitions increases, reproduction is at first fragmentary and halting; then it gains in certainty; and finally takes place smoothly and without error. The first reproduction in which this last result appears can not only be singled out as especially characteristic, but can also be practically recognised. For convenience I will designate this briefly as the first possible reproduction.
The question now is:—Does this fulfill the second condition mentioned above? Is the number of repetitions necessary to bring about this reproduction always the same, the other conditions being equivalent?
However, in this form, the question will be justly rejected because it forces upon us, as if it were an evident supposition, the real point in question, the very heart of the matter, and admits of none but a misleading answer. Anyone will be ready to admit without hesitation that this relation of dependence will be the same if perfect equality of experimental condition is maintained. The much invoked freedom of the will, at least,
