I have not given a formal list of books worth reading, nor do I intend to; one of the reasons being that the work has been done so well by others. Ever since Sir John Lubbock published his list of one hundred best books, the number of selections has been legion. Charles Eliot’s selection for his _Five Foot Shelf_ is to be commended, and a little volume by Frank Parsons _The World’s Best Books_. Of course our purpose is special:—to find the best books for making thinkers; but the remarks already made should aid the reader sufficiently in making his own selection from these lists. As previously pointed out, if the reader is studying a specialty he can usually find a fairly well selected bibliography at the end of the article on that specialty in any standard encyclopedia. * * * * * The reader probably sees clearly by now that it is impossible to do his own thinking in every case; that if he is to have sound knowledge on important questions he must have the courage to be ignorant of many things. How much trouble to go to in any particular case it is difficult to say. We can lay it down as a general principle that questions of the highest importance, such as those of which I have given a suggestive list—questions which deal with facts known or easily ascertainable, and which depend for their right solution more on thinking than on anything else—a man should solve for himself, and should take the greatest caution in so doing. On the other hand, questions of the highest importance which depend for their solution mainly on full and detailed knowledge of highly technical facts which lie outside of one’s specialty, should be dealt with by consulting authorities and taking their word for it. There still remains the great mass of questions which are relatively unimportant, but continually coming up in our daily life, the answers to which greatly influence our conduct. Time forbids us not only from thinking these out for ourselves, but even from consulting an authority—for the selection of an authority often involves almost as much intellectual responsibility as self-thinking. The only thing we can do is to accept the verdict of popular opinion.