##### Halmos, Paul R.

Mathematics is not a
deductive science --
that's a cliche.
When you try to
prove a theorem, you
don't just list the
hypotheses, and then
start to reason.
What you do is trial
and error,
experimentation,
guesswork.

I Want to Be a
Mathematician,
Washington: MAA
Spectrum, 1985.

##### Haldane, John Burdon Sanderson (1892-1964)

A time will however come (as I believe) when physiology will invade and destroy mathematical physics, as the latter has destroyed geometry.

Daedalus, or Science and the Future, London: Kegan Paul, 1923.

##### Hadamard, Jacques

Practical
application is found
by not looking for
it, and one can say
that the whole
progress of
civilization rests
on that principle.

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

##### Haldane, John Burdon Sanderson (1892-1964)

In scientific thought we adopt the simplest theory which will explain all the facts under consideration and enable us to predict new facts of the same kind. The catch in this criterion lies in the world "simplest." It is really an aesthetic canon such as we find implicit in our criticisms of poetry or painting. The layman finds such a law as dx/dt = K(d^2x/dy^2) much less simple than "it oozes," of which it is the mathematical statement. The physicist reverses this judgment, and his statement is certainly the more fruitful of the two, so far as prediction is concerned. It is, however, a statement about something very unfamiliar to the plainman, namely, the rate of change of a rate of change.

##### Hadamard, Jacques

The shortest path between two truths in the real domain passes through the complex domain.

Quoted in The Mathematical Intelligencer, v. 13, no. 1, Winter 1991.

##### Hugo Rossi

In the fall of 1972 President Nixon announced that the rate of increase of inflation was decreasing. This was the first time a sitting president used the third derivative to advance his case for reelection.

Mathematics Is an Edifice, Not a Toolbox, Notices of the AMS, v. 43, no. 10, October 1996.

##### Hilbert, David (1900)

A mathematical
theory is not ...
complete until you
have made it so
clear that you can
explain it to the
first man whom you
meet on the street.

##### H.L. Mencken

For every problem,
there is one
solution which is
simple, neat, and
wrong.

##### Hermann Weyl

Symmetry, as wide or
as narrow as you may
define its meaning,
is one idea by which
man through the ages
has tried to
comprehend and
create order,
beauty, and
perfection.

Manfred Schroeder,
*Fractals, Chaos,
Power Laws* 1991