Let it be considered how differently a science is propagated from the way in which any special talent in a family is transmitted. The bodily transmission of an individual science is something very rare. Do the sons of philologists easily become philologists? Dubito. Thus there is no such accumulation of philological capacity as there was, let us say, in Beethoven's family of musical capacity. Most philologists begin from the beginning, and even then they learn from books, and not through travels, &c. They get some training, of course.