A conventional valuation which is established as the outcome of the mass psychology of a large number of ignorant individuals is liable to change violently as the result of a sudden fluctuation of opinion due to factors which do not really make much difference to the prospective yield; since there will be no strong roots of conviction to hold it steady.

... a speculator is one who runs risks of which he is aware and an investor is one who runs risks of which he is unaware.

There is no subtler, no surer means of overturning the existing basis of society than to debauch the currency.

Markets can remain irrational longer than you can remain solvent.

The markets are moved by animal spirits, and not by reason.

Dangerous acts can be done safely in a community which thinks and feels rightly, which would be the way to hell if they were executed by those who think and feel wrongly.

In this autumn of 1919, in which I write, we are at the dead season of our fortunes.