##### Holmes, Oliver Wendell

I was just going to say, when I was interrupted, that one of the many ways of classifying minds is under the heads of arithmetical and algebraical intellects. All economical and practical wisdom is an extension of the following arithmetical formula: 2 + 2 = 4. Every philosophical proposition has the more general character of the expression a + b = c. We are mere operatives, empirics, and egotists until we learn to think in letters instead of figures.

The Autocrat of the Breakfast Table.

##### Holmes, Oliver Wendell

Certitude is not the test of certainty. We have been cocksure of many things that are not so.

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

##### Holmes, Oliver Wendell

Descartes commanded the future from his study more than Napoleon from the throne.

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

##### Hobbes, Thomas

The errors of
definitions multiply
themselves according
as the reckoning
proceeds; and lead
men into
absurdities, which
at last they see but
cannot avoid,
without reckoning
anew from the
beginning.

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

##### Hobbes, Thomas

Geometry, which is
the only science
that it hath pleased
God hitherto to
bestow on mankind
...

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

##### Hobbes, Thomas

To understand this for sense it is not required that a man should be a geometrician or a logician, but that he should be mad.

["This" is that the volume generated by revolving the region under 1/x from 1 to infinity has finite volume.]

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

##### Hobbes, Thomas

There is more in Mersenne than in all the universities together.

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

##### Hirst, Thomas Archer

10th August 1851: On Tuesday evening at Museum, at a ball in the gardens. The night was chill, I dropped too suddenly from Differential Calculus into ladies' society, and could not give myself freely to the change. After an hour's attempt so to do, I returned, cursing the mode of life I was pursuing; next morning I had already shaken hands, however, with Diff. Calculus, and forgot the ladies....

J. Helen Gardner and Robin J. Wilson, "Thomas Archer Hirst - Mathematician Xtravagant II - Student Days in Germany", The American Mathematical Monthly , v. 6, no. 100.

##### Hilbert, David (1862-1943)

The infinite! No other question has ever moved so profoundly the spirit of man.

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

##### Hilbert, David (1862-1943)

Mathematics knows no
races or geographic
boundaries; for
mathematics, the
cultural world is
one country.

In H. Eves,
Mathematical Circles
Squared, Boston:
Prindle, Weber and
Schmidt, 1972.