I remember the day my daughter (now age 24 years) discovered her feet. I had dressed her with brightly colored socks and laid her down on her back in the middle of our big bed. As she waved her feet back and forth, one foot passed through her field of view. She looked startled and was able to move the foot back into view. Over and over again, she wiggled her foot, saw it wiggle, and laughed. This was a big day for our little girl. She now knew what it felt like to wiggle her foot and that she could control its movements.
Many of the problems we solve as infants are sensorimotor ones. First, we observe the world through out eyes, but by three or four months, we start swiping at things with our hands. In a classic study in the 1960's, scientists at MIT showed that accurate reaching in cats develops only when the kittens are able to watch their own limbs as they move them. Similarly, we must see and also feel our arms and legs moving in order to control them.
Of course, most of us cannot remember the day we discovered our feet, but I made a similar discovery at 48 years of age when I learned how to move my eyes to see in 3D. I was performing a vision therapy procedure called the Brock string which taught me how to aim my two eyes at the same point in space at the same time. Most people develop this skill within the first six months of life, but being cross-eyed since infancy, I had to learn how to do this as an adult. As I aimed my two eyes together at beads located at different distances along the string, I said to the vision therapist somewhat breathlessly, "I feel my eyes moving!" I felt them moving as a team, turning in together to look at the close bead and turning out together to look at the more distant one. This moment provided me with one of the most important revelations and turning points in my vision therapy. Like my daughter, who learned what it felt like to control the movement of her feet, I learned what it felt like to control the movement of my two eyes. When I went out to my car after that vision therapy session, I saw to my astonishment that the steering wheel of the car appeared to float in its own volume of space with a palpable pocket of space between it and the dashboard. This was my first 3D experience. From that moment on, my view of the world began to transform.
To move is to solve a problem in space and time. You have to know where you and other objects are located in order to navigate around them or pick them up, and you must coordinate the movements of several limbs at once. Does this sort of problem-solving extend to other forms of intelligence? Recently, I read an interview of an author who still writes his books in longhand. He stated that he cannot divorce the physical act of setting pen to paper from the intellectual act of synthesizing his thoughts and ideas. Similarly, I sing in a chorale and we often sight-sing, that is, we are presented with a musical score and have to sing the notes. This is very difficult for me, but I have worked out a strategy. As I sing the notes, I move my fingers as if I were playing the same notes on the piano, and these movements help me to reach the proper pitch.
Today we absorb much of our knowledge through the internet, an act which requires little more than the click of a mouse. Schools have little money for classes that require thinking and moving, such as classes in the visual arts, acting, or music. Laboratories courses, emphasizing hands-on activities, are cut from our science curriculum. If we divorce our learning from our actions, will we lose important ways of thinking? After all, we were built to move, not for the mouse click.