##### Russell, Bertrand (1872-1970)

Calculus required continuity, and continuity was supposed to require the infinitely little; but nobody could discover what the infinitely little might be.

In N. Rose Mathematical Maxims and Minims, Raleigh NC:Rome Press Inc., 1988.

##### Russell, Bertrand (1872-1970)

The fact that all Mathematics is Symbolic Logic is one of the greatest discoveries of our age; and when this fact has been established, the remainder of the principles of mathematics consists in the analysis of Symbolic Logic itself.

Principles of Mathematics. 1903.

##### Russell, Bertrand (1872-1970)

A habit of basing convictions upon evidence, and of giving to them only that degree or certainty which the evidence warrants, would, if it became general, cure most of the ills from which the world suffers.

In G. Simmons Calculus Gems, New York: McGraw Hill Inc., 1992.

##### Russell, Bertrand (1872-1970)

The method of "postulating" what we want has many advantages; they are the same as the advantages of theft over honest toil.

Introduction to Mathematical Philosophy, New York and London, 1919, p 71.

##### Russell, Bertrand (1872-1970)

[Upon hearing via Littlewood an exposition on the theory of relativity:]

To think I have spent my life on absolute muck.

J.E. Littlewood, A Mathematician's Miscellany, Methuen and Co. ltd., 1953.

##### Russell, Bertrand (1872-1970)

But, you might say, "none of this shakes my belief that 2 and 2 are 4." You are quite right, except in marginal cases -- and it is only in marginal cases that you are doubtful whether a certain animal is a dog or a certain length is less than a meter. Two must be two of something, and the proposition "2 and 2 are 4" is useless unless it can be applied. Two dogs and two dogs are certainly four dogs, but cases arise in which you are doubtful whether two of them are dogs. "Well, at any rate there are four animals," you may say. But there are microorganisms concerning which it is doubtful whether they are animals or plants. "Well, then living organisms," you say. But there are things of which it is doubtful whether they are living organisms or not. You will be driven into saying: "Two entities and two entities are four entities." When you have told me what you mean by "entity," we will resume the argument.

In N. Rose Mathematical Maxims and Minims, Raleigh NC:Rome Press Inc., 1988.

##### Russell, Bertrand (1872-1970)

I wanted certainty in the kind of way in which people want religious faith. I thought that certainty is more likely to be found in mathematics than elsewhere. But I discovered that many mathematical demonstrations, which my teachers expected me to accept, were full of fallacies, and that, if certainty were indeed discoverable in mathematics, it would be in a new field of mathematics, with more solid foundations than those that had hitherto been thought secure. But as the work proceeded, I was continually reminded of the fable about the elephant and the tortoise. having constructed an elephant upon which the mathematical world could rest, I found the elephant tottering, and proceeded to construct a tortoise to keep the elephant from falling. But the tortoise was no more secure than the elephant, and after some twenty years of very arduous toil, I came to the conclusion that there was nothing more that I could do in the way of making mathematical knowledge indubitable.

##### Russell, Bertrand (1872-1970)

Work is of two kinds: first, altering the position of matter at or near the earth's surface relatively to other such matter; second, telling other people to do so. The first kind is unpleasant and ill paid; the second is pleasant and highly paid.

##### Russell, Bertrand (1872-1970)

A sense of duty is useful in work but offensive in personal relations. Certain characteristics of the subject are clear. To begin with, we do not, in this subject, deal with particular things or particular properties: we deal formally with what can be said about "any" thing or "any" property. We are prepared to say that one and one are two, but not that Socrates and Plato are two, because, in our capacity of logicians or pure mathematicians, we have never heard of Socrates or Plato. A world in which there were no such individuals would still be a world in which one and one are two. It is not open to us, as pure mathematicians or logicians, to mention anything at all, because, if we do so we introduce something irrelevant and not formal.

In J. R. Newman (ed.) The World of Mathematics, New York: Simon and Schuster, 1956.

##### Russell, Bertrand (1872-1970)

The desire to understand the world and the desire to reform it are the two great engines of progress.