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
If at times I have thought myself unfortunate, it is because of a confusion, an error. I have mistaken myself for someone else... Who am I really? I am the author of The World as Will and Representation, I am the one who has given an answer to the mystery of Being that will occupy the thinkers of future centuries. That is what I am, and who can dispute it in the years of life that still remain for me?
There is no more evil thing in this world than race prejudice, none at all. [...] It justifies and holds together more baseness, cruelty, and abomination than any other sort of error in the world.
Many a profound genius, I suppose, who fills the world with fame of his exploding renowned errors, is yet everyday posed and baffled by trivial questions at his own supper table.
If I am mistaken in my opinion that the human soul is immortal, I willingly err; nor would I have this pleasant error extorted from me; and if, as some minute philosophers suppose, death should deprive me of my being, I need not fear the raillery of those pretended philosophers when they are no more.
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?
Some positive persisting fops we know, Who, if once wrong, will needs be always so; But you with pleasure own your errors past, And make each day a critique on the last.
For knowing is spoken of in three ways: it may be either universal knowledge or knowledge proper to the matter in hand or actualising such knowledge; consequently three kinds of error also are possible.
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.