d by a Norwegian cretin, have been deemed
worthy of a place among the treasures of art-galleries and museums. Such
cases prove that the possession of one highly developed faculty does not
imply a corresponding development of all the intellectual powers.
Unintelligent, unbalanced, or even mentally deficient women, when in a
somnambulistic or hypnotic state, are able to predict future events, an
impossible feat for normal persons, or to discover the whereabouts of
objects hidden at a distance, a marvellous phenomenon, which can be
explained only by presuming the existence of a far-seeing vision, and
the working of a powerful synthetic process resembling the inspirations
of genius.

Although not a difficult task to prove the existence of traits of genius
in mentally diseased persons, the bringing to light of instances of
insanity in men of genius was a much simpler matter.

These instances, carefully classified, form the longest and most
important part of _The Man of Genius_, but it is not necessary to give
space to any of these instances here. The proofs of the connection
between genius and insanity were supplemented by data supplied by the
physical examination of a number of geniuses, compared with insane
subjects, and a careful investigation of the ethnical, social, and
geographical causes which influence the formation of both types. All the
facts elicited demonstrated their complete analogy.

But my father's studies did not stop short at the discovery of this
analogy, or that of the sources whence the diverse varieties of genius
spring, which is perhaps the most interesting part of the book, or even
at the application of the new doctrines for the purpose of clearing up
obscure points in history and shedding light on the lives of great men.
He pursued his investigations until he found the keystone of the edifice
reared by insanity and genius--epilepsy.

It is a well-known fact that a great many men of genius have suffered
from epileptic seizures and a still greater number from those symptoms
which we have shown to be the equivalent of the seizure. Julius Caesar,
St. Paul, Mahomet, Petrarca, Swift, Peter the Great, Richelieu,
Napoleon, Flaubert, Guerrazzi, De Musset, and Dostoyevsky were subject
to fits of morbid rage; and Swift, Marlborough, Faraday, and Dickens
suffered from vertigo.

But it is in the descriptions written by men of genius of their methods
of working and creating that we find the strongest resembla