This work, which belongs to the middle of the fifteenth century, is interesting as a real effort at psychology.

Leonardo makes Judas leave his seat to ask if it is he that is meant--that being the dramatic moment chosen by this prince of painters: Castagno calls attention to Judas as an undesirable member of the little band of disciples by placing him apart, the only one on his side of the table; which was avoiding the real task, since naturally when one of the company was forced into so sinister a position the question would be already answered.

Castagno indeed renders Judas so obviously untrustworthy as to make it a surprise that he ever was admitted among the disciples (or wished to be one) at all; while Vasari blandly suggests that he is the very image of the painter himself.

Other positions which later artists converted into a convention may also be noted: John, for example, is reclining on the table in an ecstasy of affection and fidelity; while the Florentine loggia as the scene of the meal was often reproduced later.
Andrea del Castagno began life as a farm lad, but was educated as an artist at the cost of one of the less notable Medici.

He had a vigorous way with his brush, as we see here and have seen elsewhere.