At twenty years of age, a selection must be made of the more promising disciples, with whom a new epoch of education will begin.

The sciences which they have hitherto learned in fragments will now be brought into relation with each other and with true being; for the power of combining them is the test of speculative and dialectical ability.

And afterwards at thirty a further selection shall be made of those who are able to withdraw from the world of sense into the abstraction of ideas.

But at this point, judging from present experience, there is a danger that dialectic may be the source of many evils.

The danger may be illustrated by a parallel case:--Imagine a person who has been brought up in wealth and luxury amid a crowd of flatterers, and who is suddenly informed that he is a supposititious son.