The physician devotes a large part of his professional life to interpreting signs. Physical signs— the various swellings or discolorations, the sounds, or tactile sensations—all must be interpreted in terms of health or disease. So, too, various laboratory tests furnish other signs which refer to physiological functions. Still other signs point not to physical ailments but to personality factors. Most obvious among these are overt behavior patterns, when, for example, a disturbed youth runs amok. Far more subtle indicators are works of art, which to the curious and perceptive onlooker may reveal a great deal about the artist.
Art is one among many forms of self-expression. The bawling infant, the destructive child, the possessive parent, the querulous oldster also are expressing themselves; but these expressions we do not call "art," for they lack a certain characteristic and distinguishing property which we can best call "esthetic." In art, relationships of line