stimuli it always responds in the same way, like reflex action in living beings, and like association in ordinary consciousness. Water always boils punctually at 100°C., and freezes at 0°C., if the pressure is 760mm. of mercury. "Canal" always makes me think of Panama and Mars--though to other people it might suggest Suez, their different experience having given them other association-couplings. But any one knowing me well, or knowing any one well, could say almost certainly what associations "canal" would have--what thought it will evoke. And the same thing is true, to a less extent, of our actions. If a man hits Jack Johnson, the latter will probably hit back. Still more certain is it that no one will hit him unless drunk or insane or in some sort of very exceptional circumstances. If, on the other hand, somebody hits me, the outcome is less certain. It will depend to a greater extent on the result of reflection and judgment--perhaps partly on my estimate of the other fellow's weight, age, training and science! Yet anyone knowing me well, and perceiving the main conditions, could predict with fair approach to accuracy what I should do. Yet I am undoubtedly a conscious being. Some actions of conscious beings, then, are predictable, if we know the conditions. Indeed, in the mass, human action is calculable with precision--witness the various kinds of insurance. Why then deny consciousness to the Matterhorn, because _all_ its actions are calculable and predictable? The difference is one of degree, not kind. And indeed _are_ all its actions predictable? The fact is, they are only hypothetically so. We say that they would be if we knew enough. But we might say the same of the actions of a man. The truth is, that if we say it of either we are arguing dangerously, from our ignorance and not from our knowledge. It is indeed as risky to say that we could predict the Matterhorn's actions _in toto_, as to say that we cannot predict the man's; for we are continually finding that matter does things which we did not formerly suspect--_e.g._ radio-activity. Clearly, we cannot predict all the activities of the Matterhorn: many may depend on undiscovered properties. So it seems that even if some human actions, such as Newton's discovery of the law of gravitation and Milton's _Paradise Lost_ and Spencer's Synthetic Philosophy and Raphael's Sistine Madonna, are strictly unpredictable, it still does not sufficiently differentiate us from the Matterhorn, which on its part also has its unpredictabilities.