A man cannot be comfortable without his own approval. There is nothing more satisfying than that sense of being completely "at home" in your own skin. When you achieve that as a natural state of "being", then you can finally look beyond yourself and fully contribute all your talents to the world.
Habit is habit and not to be flung out of the window by any man, but coaxed downstairs a step at a time. You cannot eliminate habits that no longer serve you. You can only replace them with new habits that support your goals. Moment by moment, you need to live with awareness and structure the habits that you include or exclude in your days.
He had an uncommon fondness for cats. As an old man summering in New Hampshire, Twain even rented kittens from a nearby farm to keep him company until he returned home. "If man could be crossed with the cat," said Twain, "it would improve the man, but it would deteriorate the cat." There's always something about your success that displeases even your best friends.
When I was fourteen, my father was so ignorant I could hardly stand to have him around. When I got to be twenty-one, I was astonished at how much he had learned in seven years. See what happens when you "know it all", at any stage of life? Farther down the track you may see clearly how certain personal opinions, held onto too tightly, could be fogging up the view, and providing incorrect insight. Prosperity is the best protector of principle.
Sometime, somewhere you take something to be the truth. But if you cling to it too strongly, then even when the truth comes in person and knocks on your door, you will not open it.