If the Heringian view is accepted, that heredity is only a mode of memory, and an extension of memory from one generation to another, then the repetition of its development by any embryo thus becomes only the repetition of a lesson learned by rote; and, as I have elsewhere said, our view of life is simplified by finding that it is no longer an equation of, say, a hundred unknown quantities, but of ninety-nine only, inasmuch as two of the unknown quantities prove to be substantially identical.  In this case the inheritance of acquired characteristics cannot be disputed, for it is postulated in the theory that each embryo takes note of, remembers and is guided by the profounder impressions made upon it while in the persons of its parents, between its present and last preceding development.  To maintain this is to maintain use and disuse to be the main factors throughout organic development; to deny it is to deny that use and disuse can have any conceivable effect.  For the detailed reasons which led me to my own conclusions I must refer the reader to my books Life and Habit and Unconscious Memory, the conclusions of which have been often adopted, but never, that I have seen, disputed.  A brief resume of the leading points in the argument is all that space will here allow me to give.

We have seen that it is a first requirement of heredity that there shall be physical continuity between parents and offspring.  This holds good with memory.  There must be continued identity between the person remembering and the person to whom the thing that is remembered happened.  We cannot remember things that happened to someone else, and in our absence.  We can only remember having heard of them.  We have seen, however, that there is as much bona-fide sameness of personality between parents and offspring up to the time at which the offspring quits the parent’s body, as there is between the different states of the parent himself at any two consecutive moments; the offspring therefore, being one and the same person with its progenitors until it quits them, can be held to remember what happened to them within, of course, the limitations to which all memory is subject, as much as the progenitors can remember what happened earlier to themselves.  Whether it does so remember can only be settled by observing whether it acts as living beings commonly do when they are acting under guidance of memory.  I will endeavour to show that, though heredity and habit based on memory go about in different dresses, yet if we catch them separately—­for they are never seen together—­and strip them there is not a mole nor strawberry-mark nor trick nor leer of the one, but we find it in the other also.

What are the moles and strawberry-marks of habitual action, or actions remembered and thus repeated?  First, the more often we repeat them the more easily and unconsciously we do them.  Look at reading, writing, walking, talking, playing the piano, etc.; the longer we have practised any one of these acquired habits, the more easily, automatically and unconsciously, we perform it.  Look, on the other hand, broadly, at the three points to which I called attention in Life and Habit:—­