The other kind of concentration is constructing or composing; for instance, when an artist has been told to make a very fanciful picture and he creates in his mind a creature with the face of a man, the horns of a buffalo and the wings of a bird. The material is there in his mind; he has only to put it together in order to produce a certain form. This is constructive concentration, visualizing, in other words making the mind produce something under the direction of the will.