Whenever we compare men of genius with each other, the history of those who are no more will serve as a perpetual commentary on our contemporaries.

There are, indeed, secret feelings which their prudence conceals, or their fears obscure, or their modesty shrinks from, or their pride rejects; but I have sometimes imagined that I have held the clue as they have lost themselves in their own labyrinth.

I know that many, and some of great celebrity, have sympathised with the feelings which inspired these volumes; nor, while I have elucidated the idiosyncrasy of genius, have I less studied the habits and characteristics of the lovers of literature.
It has been considered that the subject of this work might have been treated with more depth of metaphysical disquisition; and there has since appeared an attempt to combine with this investigation the medical science.

A work, however, should be judged by its design and its execution, and not by any preconceived notion of what it ought to be according to the critic, rather than the author.

The nature of this work is dramatic rather than metaphysical.