tests will select for us foods among poisons. We may trust these tests absolutely. We may safely and sometimes wisely take poisons into our bodies if we know what we are doing. By the advice of a physician, trusting in the weigher's instruments of precision, poisons may do no harm. One grain of strychnine may be an aid to vital processes; a dozen may mean instant cessation of these processes. The balance advises us as to all this. All these instruments of precision belong to science. These are examples taken from thousands of the methods of organized common sense. By means of common sense, organized and unorganized, all creatures that can move are enabled to move safely. The security of human life in its relations to environment is a sufficient answer to the "philosophic doubt" of Berkeley and Balfour as to the existence of external Nature; for if all phenomena were within the mind, no one of them could be more dangerous than another. A dream of murder is no more dangerous than a dream of an afternoon pink tea, so long as its action is confined to the limits of the dream; but the relation of life to environment is inseparable and inexorable. Cause and effect are perfectly linked. This is a world of absolute verity, and its demand is absolute obedience. Life without concessions of conditions is the philosopher's dream.
What we know as pain is the necessary signal of warning of bad results, of bad relations. Without pain life conditioned by environment would be impossible. We need such stimulus to veracity. Those dangers which are painless are the hardest to avoid; the diseases which are painless are the most difficult to cure. Misery in general is only Nature's protest against personal degradation. The way out of misery is the way into life.
In this relation must science recognize the value of ideals? The ideal in the mind tends always to go over into, action. The noble ideal discloses itself in a noble life. It is part of the wisdom of each generation, its science as well as its religion, to form the ideals of the rest. History is written in these ideals before it is come to the stage of life. An ideal is not a dream; a dream is fleeting. An ideal has the will behind it. The persistence of a lofty ideal is the central axis of the life worth living.
An old parable of the conduct of life shows man in a light skiff in a tortuous channel beset with rocks, borne by a falling current to an unknown sea. He is kept awake by the needs of his situation. As his boat bumps against the rocks he must bestir himself. If this contact were not painful he would not heed it. If it were not hurtful he would not need to heed it. Had he no power to act, he could not heed it if he would. But with sensation, will, freedom to act, narrow though the limits of freedom be, his safety rests in some degree in his own hands. That he has
