If . . . I seem to express myself dogmatically, it is only because I find it very boring to qualify every phrase with an 'I think' or 'to my mind.' Everything I say is merely an opinion of my own. The reader can take it or leave it. If he has the patience to read what follows he will see that there is only one thing about which I am certain, and this is that there is very little about which one can be certain. (Pocket Book edition, 1967, p. 9)Maugham, I think, feigned humility. If he was certain of nothing else, he must have been quite certain about how he should lead his life, which is saying quite a lot. Certainty about how to lead one's life is the most important certainty to hold, but it cannot be arrived at without introspection and self-criticism. To put it another way, a life lived willy-nilly, with only immediate gratification in mind, is likely to be chaotic and, in the end, disappointing.
Given the difficulty of ordering one's own life, it is wise to be uncertain about precisely how others should lead their lives, except to admonish (and sometimes punish) those who trespass against us. We must try to raise our children well, but we should not behave toward adults as if they were children. Paternalism toward adults is a form of consdescension. It says, in effect, "I am privileged (i.e., superior to you), and I am therefore qualified to decide how you should live your life and how others must or must not deal with you."