Expose thermometers of several kinds to one and the same temperature. One will indicate, say, 60 degrees, another as high as 100 degrees, another as low as 15 degrees. Expose the thermometers of human sensibilities, which are of myriads of different kinds, to one and the same temperature of environment. None of them will indicate the same degrees. In one and the same climate, which we think moderate, the Eskimo would be washed with perspiration, while the Hindu would shudder with cold. Similarly, under one and the same circumstance some might be extremely miserable and think it unbearable, yet others would be contented and happy. Therefore we may safely conclude that there are no definite external causes of pain and pleasure, and that there must be internal causes which modify the external.

3. The Law of Balance.--Nature governs the world with her law of balance. She puts things ever in pairs,' and leaves nothing in isolation. Positives stand in opposition to negatives, actives to passives, males to females, and so on. Thus we get the ebb in opposition to the flood tide; the centrifugal force to the centripetal; attraction to repulsion; growth to decay; toxin to antitoxin; light to shade; action to reaction; unity to variety; day to night; the animate to the inanimate. Look at our own bodies: the right eye is placed side by side with the left; the left shoulder with the right; the right lung with the left; the left hemisphere of the brain with that of the right; and so forth.

It holds good also in human affairs: advantage is always accompanied by disadvantage; loss by gain; convenience by inconvenience; good by evil; rise by fall; prosperity by adversity; virtue by vice; beauty by deformity; pain by

[1. Zenists call them 'pairs of opposites.']

pleasure; youth by old age; life by death. 'A handsome young lady of quality,' a parable in Mahaparinirvana-sutra tells us, 'who carries with her an immense treasure is ever accompanied by her sister, an ugly woman in rags, who destroys everything within her reach. If we win the former, we must also get the latter.' As pessimists show intense dislike towards the latter and forget the former, so optimists admire the former so much that they are indifferent to the latter.