
As quoted in Walden (1854) by Henry David Thoreau, Ch. 1
Attributed
Source: Tertium Organum (1912; 1922), Ch. I
Context: The most difficult thing is to know what we do know, and what we do not know.
Therefore, desiring to know anything, we shall before all else determine WHAT we accept as given, and WHAT as demanding definition and proof; that is, determine WHAT we know already, and WHAT we wish to know.
In relation to the knowledge of the world and of ourselves, the conditions would be ideal could we venture to accept nothing as given, and count all as demanding definition and proof. In other words, it would be best to assume that we know nothing, and make this our point of departure.
But unfortunately such conditions are impossible to create. Knowledge must start from some foundation, something must be recognized as known; otherwise we shall be obliged always to define one unknown by means of another.
As quoted in Walden (1854) by Henry David Thoreau, Ch. 1
Attributed
Confucius, as quoted in Walden (1854) by Henry David Thoreau, Ch. 1
Misattributed
“Far more crucial than what we know or do not know is what we do not want to know.”
Source: Value-free science?: Purity and power in modern knowledge, 1991, p. 13
“What we know is not much. What we do not know is immense.”
"Ce que nous connaissons est peu de chose, ce que nous ignorons est immense."
Allegedly his last words, reported in Joseph Fourier's "Éloge historique de M. le Marquis de Laplace" (1829) with the comment, "This was at least the meaning of his last words, which were articulated with difficulty." Quoted in Augustus De Morgan's Budget of Paradoxes (1866).
“Western Civ,” p. 18.
Giants and Dwarfs (1990)