De Divinatione

Cicero's De Divinatione (Latin, "Concerning Divination") is a philosophical treatise in two books written in 44 BC. It takes the form of a dialogue whose interlocutors are Marcus (speaking mostly in Book II) and his brother Quintus.

Cicero concerns himself in some detail with the types of divination, dividing them into the "inspired" type (Latin furor, Gk. mania, "madness"), especially dreams, and the type which occurs via some form of skill of interpretation (i.e., haruspicy, extispicy, augury, astrology, and other oracles).

Book I deals with Quintus' apology of divination (in line with his essentially Stoic beliefs), while Book II contains Marcus' refutation of these from his Academic philosophical standpoint.

It is notable as one of posterity's primary sources on the workings of Roman religion. It also includes a fragment of Cicero's poem on his own consulship.

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