MacTutor
[about him:]
It is rare to find learned men who are clean, do not stink and have a sense of humour.
Nothing is more important than to see the sources of invention which are, in my opinion more interesting than the inventions themselves.
Musica est exercitium arithmeticae occultum nescientis se numerare animi
The pleasure we obtain from music comes from counting, but counting unconsciously. Music is nothing but unconscious arithmetic.
He who understands Archimedes and Apollonius will admire less the achievements of the foremost men of later times.
In symbols one observes an advantage in discovery which is greatest when they express the exact nature of a thing briefly and, as it were, picture it; then indeed the labor of thought is wonderfully diminished.
The art of discovering the causes of phenomena, or true hypothesis, is like the art of decyphering, in which an ingenious conjecture greatly shortens the road.
Although the whole of this life were said to be nothing but a dream and the physical world nothing but a phantasm, I should call this dream or phantasm real enough, if, using reason well, we were never deceived by it.
The soul is the mirror of an indestructible universe.
The imaginary number is a fine and wonderful resource of the human spirit, almost an amphibian between being and not being.
Therefore, I have attacked [the problem of the catenary] which I had hitherto not attempted, and with my key [the differential calculus] happily opened its secret.
Taking mathematics from the beginning of the world to the time of Newton, what he has done is much the better half.
The art of discovering the causes of phenomena, or true hypothesis, is like the art of decyphering, in which an ingenious conjecture greatly shortens the road.
Miracles are not to be multiplied beyond necessity.
The dot was introduced as a symbol for multiplication by Leibniz. On July 29, 1698, he wrote in a letter to Johann Bernoulli: "I do not like X as a symbol for multiplication, as it is easily confounded with x ..."
What is is what must be.
It is unworthy of excellent men to lose hours like slaves in the labor of calculation which could be relegated to anyone else if machines were used.