ABSTRACT
This chapter explores personal recollections, remarks about Zing-Yang Kuo's theoretical and empirical work, and the bearing of his metatheoretical considerations on the contemporary notion of developmental science. Kuo's procedure not only preserved the integrity of the embryo, it also allowed him to observe how the embryo's behavior was affected by its environment, principally the amniotic sac, in which the embryo was enclosed, and the yolk sac, a near neighbor of the embryo. Kuo gave a talk in which he criticized the adequacy of unconditioned and conditioned reflexes, and proposed instead a more developmental notion of "gradients of response" as the basic analytic unit. Kuo's technique involved cutting the shell off the top of the egg and coating the inner shell membrane of the air space below with liquefied Vaseline to render it transparent. Kuo was a well-known academic in China, so long before leaving, he had discussed with Chou En-Lai, one of the communist leaders.
