And now we see what constitutes the object of insight. This is, in part, a common experience, as in the case of sense-perception and aesthetic intuition, since to perceive another's feeling is implicitly to cognize the external conditions of a common insight. But this is clearly not the whole, nor even the main part of objective reality in this act of cognition. An intuitive insight differs from a sense-perception in that it involves an immediate assurance of the existence of a feeling presentatively known, though not to our own minds. The object in insight is thus a presentative feeling as in introspection, though not our own, but another's. And so it differs from the object in sense-perception in so far as this last involves sense-experiences, as muscular and tactual feelings, which are not _at the moment_ presentatively known to any mind. _Illusions of Insight._ And now we are in a position, perhaps, to define an illusion of insight, and to inquire whether there is anything answering to our definition. An illusory insight is a quasi-intuition of another's feelings which does not answer to the internal reality as presentatively known to the subject himself. In spite of the errors of introspection dealt with in the last chapter, nobody will doubt that, when it is a question between a man's knowing what is at the moment in his own mind and somebody else's knowing, logic, as well as politeness, requires us to give precedence to the former. An illusion of insight, like the other varieties of illusion already dealt with, may arise either by way of wrong suggestion or by way of a warping preconception. Let us look at each of these sources apart. Our insights, like our perceptions, though intuitive in form, are obviously determined by previous experience, association, and habit. Hence, on its passive side, an illusion of insight may be described as a wrong interpretation of a new or exceptional case. For example, having associated the representation of a slight feeling of astonishment with uplifted eyebrows, we irresistibly tend to see a face in which this is a constant feature as expressing this particular shade of emotion. In this way we sometimes fall into grotesque errors as to mental traits. And the most practised physiognomist may not unfrequently err by importing the results of his special circle of experiences into new and unlike cases. Much the same thing occurs in language. Our timbre of voice, our articulation, and our vocabulary, like our physiognomy, have about them something individual, and error often arises from overlooking this, and hastily reading common interpretations into exceptional cases. The misunderstandings that arise even among the most open and confiding friends sufficiently illustrate this liability to error.