But the degeneration may go further still. “There is a story,” writes Huxley, “which is credible enough, though it may not be true, of a practical joker, who, seeing a discharged veteran carrying home his dinner, suddenly called out ‘Attention!’ whereupon the man instantly brought his hands down, and lost his mutton and potatoes in the gutter.” Huxley calls this an =artificial reflex= action; and indeed the organism responds, in such cases of thorough drill, as fatally and automatically as in the physiological reflexes, and with as little apprehension of the nature of the stimulus; there is nothing to choose, psychologically, between this direct response to the word ‘Attention!’ and the blinking of the eye in response to a threatened blow, or the snatching back of the hand from a hot surface, or the withdrawal of the foot when the sole is tickled. From the psychological point of view, impulsive action, instinctive action and artificial reflex all shade off into one another; and the artificial and physiological reflexes are indistinguishable. Only, as we know, _the artificial reflex has a mental history_; the word ‘Attention!’ had been called out many thousand times before it became a compelling suggestion. What, then, of the =physiological reflex=? Has it, too, a mental history, extending beyond the individual to the race; is it a racially degenerate impulsive action? or does it belong to a class apart, purely physiological in character, and without right to mention in a text-book of psychology? The answer to these questions must be speculative; and speculation, as is almost always the case, has swung between opposed extremes. Some psychologists teach that all action has its origin in the physiological reflex; the organism at first moved reflexly, automatically, fatally; and then, later, mental processes were somehow ‘imported’ into its activities. Others hold that all organic movements were originally of the impulsive sort; the physiological reflex, so far from being primary, is a late development, the final term in a series which begins with movement of a large, diffuse sort, accompanied by mental processes, and which ends with precise, local movement devoid of mental correlates. Both these views are open to objection from the biological side; and it seems reasonable to suppose that _the earliest movements of the earliest organisms were of two kinds_: some were bare reflexes, or—to use the newer word—physiological ‘tropisms’; others, however scanty and undifferentiated their mental accompaniment, were still of the nature of impulsive actions. If this mediating view be adopted, as a working hypothesis, the zoologist and the comparative psychologist must join forces, to trace the racial history of the physiological reflexes, and to determine what part of our human equipment is ultimately tropistic, and what part may be referred back to earlier impulses.