"'Sic oculos, sic ille manus, sic ora ferebat'; but scarcely less often the differences which distinguish children both from their parents and from one another. We are told of similar mental peculiarities running in families, and again of a tendency, as in the animals, to revert to a common or original stock. But we have a difficulty in distinguishing what is a true inheritance of genius or other qualities, and what is mere imitation or the result of similar circumstances. Great men and great women have rarely had great fathers and mothers. Nothing that we know of in the circumstances of their birth or lineage will explain their appearance. Of the English poets of the last and two preceding centuries scarcely a descendant remains,mdash;none have ever been distinguished. So deeply has nature hidden her secret, and so ridiculous is the fancy which has been entertained by some that we might in time by suitable marriage arrangements or, as Plato would have said, `by an ingenious system of lots,' produce a Shakespeare or a Milton. Even supposing that we could breed men having the tenacity of bulldogs, or, like the Spartans, `lacking the wit to run away in battle,' would the world be any the better?."