When you have observed your mechanisms, you will notice that you are usually very kind toward yourself (through inner considering, justification, etc.) and quite harsh with other people (or indifferent, which is no better). In our everyday life, it is very difficult for us to stop lying. Every discussion, every story or account we give of something (especially when it concerns ourselves) may be tinged with lying - in our exaggerations, half-truths, and so on. You are only obliged to express the truth about other people when this is done in order to aid their evolution, to help them to change. Each person is entitled to the truth he is capable of understanding. The truth concerning ourselves is the fundamental precondition for all possible evolution on the Path.