The satisfaction they afford must be very great, and it probably has its basis in the feeling of his own power generated by the movements originated by the child himself (changes of place, of position, of form) and in the proud feeling of being a cause. This is not mere playing, although it is so called; it is _experimenting_. The child that at first merely played like a cat, being amused with color, form, and movement, has become a _causative being_. Herewith the development of the _"I"-feeling_ enters upon a new phase; but it is not yet perfected. Vanity and ambition come in for the further development of it. Above all, it is _attention_ to the _parts of his own body_ and the _articles of his dress_, the nearest of all objects to the child's eye, that helps along the separation in thought of the child's body from all other objects. I therefore made special observation of the directing of his look toward his own body and toward the mirror. In regard to the first I took note, among other facts, of the following: _17th week._--In the seizing movements, as yet imperfect, the gaze is fixed partly on the object, partly on _his own hand_, especially if the hand has once seized successfully. _18th week._--The very attentive regarding of the fingers in seizing is surprising, and is to be observed daily. _23d week._--When the infant, who often throws his hands about at random in the air, accidentally gets hold of one hand with the other, he regards attentively both his hands, which are often by chance folded. _24th week._--In the same way the child fixes his gaze for several minutes alternately upon a glove held by himself in his hands and upon his own fingers that hold it. _32d week._--The child, lying on his back, _looks_ very frequently _at_ his _legs_ stretched up vertically, especially at his _feet_, as if they were something foreign to him. _35th week._--In every situation in which he can do so, the child tries to grasp a foot with both hands and carry it to his mouth, often with success. This monkey-like movement seems to afford him special pleasure. _36th week._--His own hands and feet are no more so frequently observed by him without special occasion. Other new objects attract his gaze and are seized. _39th week._--The same as before. In the bath, however, the child sometimes looks at and feels of _his own skin_ in various places, evidently taking pleasure in doing so. Sometimes he directs his gaze to his legs, which are bent and extended in a very lively manner in the most manifold variety of positions. _55th week._--The child looks for a long time attentively at a person eating, and follows with his gaze every movement; grasps at the person's face, and then, after _striking himself on the head_, fixes his gaze on his own hands. He is fond of playing with the fingers of the persons in the family, and delights in the bendings and extensions, evidently comparing them with those of his own fingers.