Joseph-Louis Lagrange quotes:

It has cost them but a moment to cut off that head; but a hundred years will not be sufficient to produce another like it.

"Newton was the greatest genius that ever existed, and the most fortunate, for we cannot find more than once a system of the world to establish."

As long as algebra and geometry have been separated, their progress have been slow and their uses limited; but when these two sciences have been united, they have lent each mutual forces, and have marched together towards perfection.

The ordinary operations of algebra suffice to resolve problems in the theory of curves.

If I had inherited a fortune I should probably not have cast my lot with mathematics.

I do not know. [summarising his life's work]

It took the mob only a moment to remove his head; a century will not suffice to reproduce it.

I regarded as quite useless the reading of large treatises of pure analysis: too large a number of methods pass at once before the eyes. It is in the works of application that one must study them; one judges their utility there and appraises the manner of making use of them.

The reader will find no figures in this work. The methods which I set forth do not require either constructions or geometrical or mechanical reasonings: but only algebraic operations, subject to a regular and uniform rule of procedure.