Speak not harshly to anyone. Those thus addressed will retort. Painful, indeed, is vindictive speech. Blows in exchange may bruise you.
True wisdom is less presuming than folly. The wise man doubteth often, and changeth his mind; the fool is obstinate, and doubteth not; he knoweth all things but his own ignorance… To be satisfied with a little, is the greatest wisdom; and he that increaseth his riches, increaseth his cares; but a contented mind is a hidden treasure, and trouble findeth it not.
The guru cannot awaken you; all that he can do is to point out what is. The guru can give you words; he can give you an explanation, the symbols of the mind, but the symbol is not the real, and if you are caught in the symbol, you will never find the way.

