“Madness, good, bad, or merely medical, underlies a great deal of Renaissance thought, worship, morals, literature and humour… Aristotle believed that many madmen, and all geniuses, were melancholic, an assertion he explained with the help of Plato: he took the inspiration of the true genius to be one of the good ‘manias’ which Socrates praised in the Phaedrus – a form of extatic madness closely allied to the raptures experienced by seers, prophets, poets and lovers.” – M. A. Screech, Montaigne and Melancholy.
The Greek word for mania was translated as “furor” by the Romans and its range includes both the mad fury of Hercules, who slaughtered his children, and the mad fury of Ajax, convenient in combat and battle but disastrous elsewhere.
The doctrine of melancholic inspiration was introduced into Italy by Gemistus Plethon and transmitted by Marsilio Ficino (1433-1499) in the court of Cosimo de’ Medici.
The most famous and admired examples of melancholic inspiration were Socrates and Plato, who were held by many a scholar to be enlightened pagans on a par with the saints or even, in the case of Socrates, according to Erasmus (no less), prefigurations of Christ.
Montaigne (1533-1592), however, was able to take advantage of the discovery and translation into Latin of the Hypotyposes of Pyrrho, an outline of the doctrines of the sceptical philosophy of the Greek philosopher, Pyrrho, which was published by Henricus Stephanus in Geneva in 1562, in order to undermine the Ficinian doctrine that claimed an equal status for the inspirations of the enlightened pagans with the extacies of the Christian mystics.
The influence of both Ficino and Montaigne were felt in England during the period we know as the English Renaissance, and themes of scepticism and melancholy reoccur in the plays of Shakespeare, Hamlet being the prime example.