Comprehend their Dispositions with whom you deal so as to know their intentions... The melancholy man always foresees misfortunes, the backbiter scandals; having no conception of the good, evil offers itself to them. A man moved by passion always speaks of things differently from what they are; it is his passion speaks, not his reason.
Baltasar Gracián, 1647 (tr. Joseph Jacobs, 1892)
The living half of this counsel is sound and needs no updating: know the temperament of the person you are dealing with, because a mind ruled by melancholy, malice, or passion reports the world through that filter rather than as it is, so you must decode the speaker to weigh the speech. That much survives intact, and it lives on in maxims 49, 224, and 291, which read behaviour rather than appearance. What does not survive is the tail this entry deliberately leaves out: the physiognomy, the claim that character can be read from a face, that the misshapen are to be distrusted, that beauty and folly go hand in hand. That is discredited pseudoscience of its century, kept here for completeness only, never as instruction. Read temperament and behaviour; do not read faces.