_What is the proper criterion for determining right and wrong conduct?_ Or even less dogmatic: Can there be a criterion for determining right and wrong conduct, and what is it? Somewhat allied with the ethical problem is that problem of problems: how to live? By this is meant how to put the most into life and get the most out of it; what vocation to follow; what hobbies, amusements, avocations to take up; how to plan time by months, by weeks, by days, by hours. How much time and energy do certain activities deserve? How much can we afford to give them? Restated: what activities are of most worth? Of course every one does think of problems connected with the art of living. But he thinks of them as little unconnected questions. Barely indeed does any one go about the solution of the general problem of living in an orderly, systematic manner. To insist upon the broad practical bearings of the problem would be unnecessary, absurd. By its very nature it is the most “practical” question we can ask. Any particular solution or treatment may be impractical, but this does not affect the question itself. _What are the respective influences of environment (education, experience, etc.) and innate tendencies in determining character?_ Which is the greater determinant? _Does pleasure depend upon the satisfaction of instinctive desires, or do desires for certain activities depend upon the pleasure accompanying the previous performance of such activities?_ Does an activity or the possession of an object give us pleasure because we have previously desired it, or do we desire an activity or an object because we have previously obtained pleasure from it? Or do pleasure and desire interact, and just how? The solution of this psychological problem is of tremendous importance in ethics. _Does the mind depend entirely on the brain?_ That is, are all thoughts, emotions, feelings, due to material changes in the brain? The answer we give to this problem may determine our answer to the question of immortality. _What knowledge is of most worth?_ I have so fully discussed the importance of this question and the method of proceeding with its solution that further explanation is needless.