If I were to suggest that between the Earth and Mars there is a china teapot revolving about the sun in an elliptical orbit, nobody would be able to … - Bertrand Russell

Whatever we know without inference is mental.

I should like to say two things. One intellectual and one moral. The intellectual thing I should want to say to them is this: "When you are studying any matter, or considering any philosophy, ask yourself only: What are the facts, and what is the truth that the facts bear out. Never let yourself be diverted, either by what you wish to believe, or by what you think would have beneficent social effects if it were believed; but look only and solely at what are the facts." That is the intellectual thing that I should wish to say. The moral thing I should wish to say to them is very simple; I should say: "Love is wise – Hatred is foolish." In this world, which is getting more and more closely interconnected, we have to learn to tolerate each other. We have to learn to put up with the fact, that some people say things we don't like. We can only live together in that way. But if we are to live together, and not die together, we must learn a kind of charity and a kind of tolerance which is absolutely vital, to the continuation of human life on this planet.

I do not wish to seem to end upon a note of cynicism. I do not deny that there are better things than selfishness, and that some people achieve these things. I maintain, however, on the one hand, that there are few occasions upon which large bodies of men, such as politics is concerned with, can rise above selfishness, while, on the other hand, there are a very great many circumstances in which populations will fall below selfishness, if selfishness is interpreted as enlightened self-interest. And among those occasions on which people fall below self-interest are most of the occasions on which they are convinced that they are acting from idealistic motives. Much that passes as idealism is disguised hatred or disguised love of power. When you see large masses of men swayed by what appear to be noble motives, it is as well to look below the surface and ask yourself what it is that makes these motives effective. It is partly because it is so easy to be taken in by a facade of nobility that a psychological inquiry, such as I have been attempting, is worth making. I would say, in conclusion, that if what I have said is right, the main thing needed to make the world happy is intelligence. And this, after all, is an optimistic conclusion, because intelligence is a thing that can be fostered by known methods of education.