We should not pretend to understand the world only by the intellect; we apprehend it just as much by feeling. Therefore, the judgment of the intellect is, at best, only the half of truth, and must, if it be honest, also come to an understanding of its inadequacy.

Variant translation: We should not pretend to understand the world only by the intellect. The judgement of the intellect is only part of the truth. - Psychological Types, or, The Psychology of Individuation (1921)