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sequence, not causation; he said that if a ball moved after it was hit by a bat, you should not say that the blow. of the bat caused the movement, but only that it was followed by the movement. This extreme scepticism came out strongly in some of the great men of the nineteenth century, a re-action from the ready credulity and many unproved assumptions of the Middle Ages. The reaction had its use, but is now gradually passing away, as extremes ever do.
The idea of causation arises naturally in the human mind, though unprovable by the senses; when a phenomenon has been invariably followed by another phenomenon for long periods of time, the two become linked together in our minds, and when one appears, the mind, by association of ideas, expects the second; thus the fact that night has been followed by day from time. immemorial gives us a firm conviction.
CAUSATION
