# Philosophy and Fun of Algebra/Chapter 8

CHAPTER VIII THE LIMITS OF THE TEACHER'S FUNCTION
One of the greatest causes of mental and moral confusion, as well as of absolute insanity, in modern Europe, is the fact that numbers of people plunge into the second and third great Hebrew algebras before they rightly understand the first. Even if they are silent about their results, this distracts their own minds, and sows the seeds of bad habits and mental confusion in their own constitutions. Many of these people give to the world their own wild guesses about the second and third algebras, and that puts the rest of the world into confusion. We are, therefore, not going to enter on the question of the second algebra till I have provided you with the possibility of understanding and practising the first. In the next few chapters I hope to give you a series of stories of people who used, and sometimes mis-used, the algebra of Moses, in order that you may see how to work the rules strictly and how mistakes might creep in.
​But, before we begin our stories, there is one principle to which I must call your attention: it is the business of your teachers at school to see that you acquire skill in using certain implements or tools; it is not their business nor mine to decide what use you shall make, when you are grown up, of the skill which you have acquired. It is their business to see that you learn to read and to speak properly; it is not their business to decide beforehand whether you shall recite in public or only read to your own family and your sick friends. It is their business to see that you know how to sew; but not to settle whether you shall, in future, make, your own clothes or work for the poor. So it is with the tools of the mind, such as algebra and logic. It is our business to see that you know how to use algebraic and logical method accurately and skilfully; it is not our business to decide whether, in the future, you shall use your skill to deceive other people or to show them the truth. It is our business to see that you do not deceive yourself, because deceiving yourself distorts your brain and ruins the possibility of using logical ​methods skilfully to arrive at the knowledge of truths.
When you have found out a truth, then the question whether you shall or shall not tell it to other people is a matter of conscience. You will have to settle it alone with the Great Power which no man knows. Self-deception, slipshod logic, and bad algebra are things which it is the business of your elders to protect you from while you are young, in order that you may not lose the power of being honest in case you wish to be so. My business is not to judge what is good or bad conduct, but to see that you learn how to be perfectly honest with yourself. I wish you to notice this, because in the books of the Hebrew algebra you will sometimes find good kind people spoken of very harshly; and some of the most dishonest and selfish people in the world praised and spoken of as blessed. This puzzles many good people, because they choose to fancy that the Hebrew books are sermons about right and wrong feelings; and do not like to recognise that they are really about the algebra of logic.
​As I said before, people who really conduct their minds strictly according to the algebra of logic are very prone to grow kindness and honesty towards other people, without thinking about it, as a matter of taste, of choice. They like being kind and honest better than being selfish and dishonest, and they become kind and honest without thinking much about it. But honesty to other people and honesty to yourself are two different things, and must be kept apart in your mind, just as, in physiology class, you keep apart the flesh of an animal and its skin. You believe that if the flesh is thoroughly healthy it will grow a good skin; but, while you are studying, you do not mix up statements about the one with guesses about the other. If we find that a man's logic was good, and his conduct what we should call bad, we must do what a doctor would do if he found a spot on a patient's skin which he could not account for by anything wrong in his circulation or digestion. He ought not to say either, "That spot is not there," or, "I suppose it is right that spot should be there," nor, on the other hand, to jump to the ​conclusion that that patient had been eating some particularly unwholesome thing. He ought to register in his mind, as one of his data, the fact of his own ignorance of how that spot came there. I shall have to tell you in another chapter the story of one of the most selfish and deceitful persons that ever lived, as to his conduct towards other people, but who was said to be blessed, apparently for no reason except that he was absolutely straight with his logic and honest with himself.
Besides, no one who is consciously and deliberately dishonest to serve his own selfish purposes can ever do as much harm to other people as is done every day by men and women who have muddled their own brains with crooked logic.