Eratosthenes's only tools were sticks, eyes, feet, and brains; plus a zest for experiment. With those tools he correctly deduced the circumference of the Earth, to high precision, with an error of only a few percent. That's pretty good figuring for 2200 years ago.
What is this self-inside us, this silent observer, severe and speechless critic, who can terrorize us, and urge us onto futile activity, and in the end, judge us still more severely for the errors into which his own reproaches drove us?
They (i. e., the Pythagoreans) did not advocate the free confrontation of conflicting points of view. Instead, like all orthodox religions, they practised a rigidity that prevented them from correcting their errors.
Were half the power that fills the world with terror, Were half the wealth bestowed on camps and courts, Given to redeem the human mind from error, There were no need of arsenals or forts.
Delusions, errors and lies are like huge, gaudy vessels, the rafters of which are rotten and worm-eaten, and those who embark in them are fated to be shipwrecked.
In a bull market, one must avoid the error of the preening duck that quacks boastfully after a torrential rainstorm, thinking that its paddling skills have caused it to rise in the world. A right-thinking duck would instead compare its position after the downpour to that of the other ducks on the pond.
In [chess], where the pieces have different and "bizarre" motions, with various and variable values, what is only complex, is mistaken (a not unusual error) for what is profound
When we look at the matter from another point of view, great caution would seem to be required. For the habit of lightly changing the laws is an evil, and, when the advantage is small, some errors both of lawgivers and rulers had better be left; the citizen will not gain so much by making the change as he will lose by the habit of disobedience.
It is not to everyone's taste that truth should be pronounced pleasant. But at least let no one believe that error becomes truth when it is pronounced unpleasant.
As the strata of the earth preserve in succession the living creatures of past epochs, so the shelves of libraries preserve in succession the errors of the past and their expositions, which like the former were very lively and made a great commotion in their own age but now stand petrified and stiff in a place where only the literary palaeontologist regards them.