What is the use in our talking about occult power if we have not power over our moods? Practise on moods. As an exercise, some time when you are active, force yourself to be lazy. When you are lazy and not tired, force yourself to be active. Natural fatigue should not be pressed too far, it is a mere reaction; but indolence is not fatigue. It is in the physical what melancholy is in the mental. As another exercise, when your mind circles round and round something, switch it off as you would switch off an electric light. Turn and think of something else. You can do it. And, by the way, one of the best cures for melancholy is an hour of mathematical calculations. I defy anybody to be melancholy in the arms of geometry or trigonometry. Why? You cannot think in mathematical terms and of yourself at the same time. People always think of themselves when they are melancholy. But you tell me that you became melancholy the other day in thinking about a friend who had lost her job. Think again. By wondering what you could do for this friend and whether you could afford it, you began to fear.... Is it not so? You may be sad because a friend is in trouble, but you cannot be melancholy for anybody but yourself. Another can make you melancholy by making you morbid and fearful. Our thoughts are so chained to our ego that it is difficult for them to escape for long. But are you ever melancholy when creating imaginatively a scene in a book? Could you be melancholy while figuring the “polar elevation” of a planet, or computing one of those converse “primary directions”? I see you smile. When you are engaged with figures you forget yourself. Now take my advice. When auto-suggestion is powerless to conquer melancholy, draw up an astrological figure in a low latitude with that table of oblique ascensions that I saw you using yesterday, and work out the converse primaries and the longitude of Vulcan. You remind me that when on earth I had small interest in astrology. But I am talking about mathematical calculations. LETTER XXV COMPENSATORY PLAY _February 1, 1918._ I HAVE looked in on you occasionally during the last few weeks, pleased with your resting for a time. The ambitious and energetic are prone to underestimate the value of occasional idleness. You cannot run even a machine all the time without oil and rest. Neither can the most vigorous engineer-soul run its brain and body too long without letting them cool. The farmer knows when to let a field lie fallow.