Lastly, the consideration just alluded to is, that civilized man enjoys an advantage over savage man far in advance even of those which arise from a settled state of society, incentives to intellectual training, and so on. This inestimable advantage consists in the art of writing, _and the consequent transmission of the effects of culture from generation to generation_. Quite apart from any question as to the hereditary transmission of acquired characters, we have in this _intellectual_ transmission of acquired _experience_ a means of accumulative cultivation quite beyond our powers to estimate. For, unlike all other cases where we recognize the great influence of individual use or practice in augmenting congenital "faculties" (such as in the athlete, pianist, &c.), in this case the effects of special cultivation do not end with the individual life, but are carried on and on through successive generations _ad infinitum_. Hence, a civilized man inherits mentally, if not physically, the effects of culture for ages past, and this in whatever direction he may choose to profit therefrom. Moreover--and I deem this an immensely important addition--in this unique department of purely intellectual transmission, a kind of non-physical natural selection is perpetually engaged in producing the best results. For here a struggle for existence is constantly taking place among "ideas," "methods," and so forth, in what may be termed a psychological environment. The less fit are superseded by the more fit, and this not only in the mind of the individual, but, through language and literature, still more in the mind of the race. "A Newton, a La Place, a Gauss, or a Cayley," would all alike have been impossible, but for a previously prolonged course of mental evolution due to the selection principle operating in the region of mathematics, by means of continuous survivals of the best products in successive generations. And, of course, the same remark applies to art in all its branches[22]. [22] In Prof. Lloyd Morgan's _Animal Life and Intelligence_ there is an admirable discussion on this subject, which has been published since the above was written. The same has to be said of Weismann's Essay on Music, where much that I have here said is anticipated. With the views and arguments which Mr. Mivart has forcibly set forth I have already dealt to the best of my ability in a work on _Mental Evolution in Man_.