Since writing these three books I have published nothing on the connection between heredity and memory, except a few pages of remarks on Mr. Romanes’ “Mental Evolution in Animals” in my book, {23a} from which I will draw whatever seems to be more properly placed here. I have collected many facts that make my case stronger, but am precluded from publishing them by the reflection that it is strong enough already. I have said enough in “Life and Habit” to satisfy any who wish to be satisfied, and those who wish to be dissatisfied would probably fail to see the force of what I said, no matter how long and seriously I held forth to them; I believe, therefore, that I shall do well to keep my facts for my own private reading and for that of my executors. I once saw a copy of “Life and Habit” on Mr. Bogue’s counter, and was told by the very obliging shopman that a customer had just written something in it which I might like to see. I said of course I should like to see, and immediately taking the book read the following—which it occurs to me that I am not justified in publishing. What was written ran thus:— “As a reminder of our pleasant hours on the broad Atlantic, will Mr. — please accept this book (which I think contains more truth, and less evidence of it, than any other I have met with) from his friend —?” I presume the gentleman had met with the Bible—a work which lays itself open to a somewhat similar comment. I was gratified, however, at what I had read, and take this opportunity of thanking the writer, an American, for having liked my book. It was so plain he had been relieved at not finding the case smothered to death in the weight of its own evidences, that I resolved not to forget the lesson his words had taught me. The only writer in connection with “Life and Habit” to whom I am anxious to reply is Mr. Herbert Spencer, but before doing this I will conclude the present chapter with a consideration of some general complaints that have been so often brought against me that it may be worth while to notice them. These general criticisms have resolved themselves mainly into two.