Hippocrates, Vol. IV (Loeb Classical Library)

...a slight and venial one. As stated above, oracular responses seem to have started the fashion of purposefully hiding thought, but it was sustained by the Greeks' love of solving puzzles and having something truly difficult with which to exercise their brains.

It has already been pointed out, in the introduction to Decorum, that certain (probably late) tracts in the Corpus are intentionally difficult, but the reason for their difficulties may well be a desire to keep secret the ritual or liturgy of a guild. Decorum, Precepts, and Law are in a category of their own. This explanation, however, will not apply to the obscure passages in Humours. This work has nothing to do with secret societies. It is a series of notes which, however disjointed or unconnected, are severely practical. Their obviously utilitarian purpose makes their obscurity all the more difficult to understand; a textbook, one might suppose, ought at least to be clear. Yet, when we have made allowances for hasty writing and for the natural obscurity of all abbreviated notes, there remains in Humours a large residue of passages in which the difficulties appear to be intentional. The fact that these passages¹ are sometimes written in a rather lofty style seems to suggest an explanation. Humours is akin—though not closely so—to Nutriment; it is aphoristic after the manner of Heracleitus "the Dark." This thinker adopted the oracular style when expounding his philosophical system, and certain later thinkers...

¹ I seem to detect the characteristics to which I refer chiefly in Chapter I, and in the various lists of symptoms, etc.