'Bad money drives out good.' From one of the founding fathers of modern economics.

'Work expands so as to fill the time available for its completion.'

'Plurality is not to be assumed without necessity.', or: the simplest explanation is the best/correct one.

Employment of the mathematics of probability (a bet) to try to answer the question of whether God exists or not.

Since it takes some time to travel half the distance between A and B, and since the remaining distance can always be divided in half, it is impossible to ever reach B.

Idealism, the bright and hopeful world of truths or ideas (ideals), which lies beyond the underground den in which human beings are imprisoned.

A three-pronged, philosophical utensil for separating interesting problems from bogus ones.

It is possible to determine the density of an object, by comparing its weight with the amount of water it displaces.

Proof, using arithmetic, that the completeness and consistency of arithmetic cannot be proved.

Sigmund Freud's 'abuse' of a Greek legend to explain his theory on a particular neurosis.

Predictable reactions, or conditioned behaviour occasioned by a stimulus.

19th. Century studies on inheritance in the humble pea plant by an Austrian monk produced these.

Three laws of force and motion, formulated by an English physicist, who is often called the greatest scientist in history.

The idea of Heliocentricism, first promulgated by Polish astronomer, Mikołaj Kopernik.

The square of the hypoteneuse (in a right-angled triangle) is equal to the sum of the squares of the other two sides.

## Show Comments