That certainly borrows from Socrates: "I know one thing: that I know nothing."
W B Yeats: "The best lack all conviction, and the worst / Are full of passionate intensity."
Bertrand Russell: "The fundamental cause of the trouble is that in the modern world the stupid are cocksure while the intelligent are full of doubt."
Charles Darwin: "Ignorance more frequently begets confidence than does knowledge."
the Tao Te Ching: "To know that you do not know is highest. To not know but think you know is flawed. ... The sages are without fault, because they recognize the fault as a fault".
(Semi-interestingly, I can't find anything very close to this idea in the biblical books of Proverbs and Ecclesiastes -- the former sees certainty as something to aspire to, and the latter is just equally down on everyone, wise and foolish alike.)
do not doubt the one
who says he is afraid
but be afraid of the one
who says he knows no doubtFor example, "He who questions training... only trains himself at asking questions."
Or Romans 1:22. "While claiming to be wise, they became fools." Rom 12:16 "Do not be wise in your own estimation"
Is 5:21 "Woe! Those who are wise in their own eyes, prudent in their own view!"
1 Cor 1:21 "For since in the wisdom of God the world did not come to know God through wisdom, it was the will of God through the foolishness of the proclamation [crucifixion] to save those who have faith." Wisdom ain't all it's cracked up to be
I always read this quote by Yeats as a lamentation about the status of the world, similar to your Russel quote that's a bit more explicit. But the Socrates quote is clearly not in this vein...
It never occurred to me before that Yeats might be more in line with Socrates than with Russell. You can read him as praising the best for their lack of conviction and condemning the worst for their passion. I like that reading much better. (Of course, I've never read the source, just heard it quoted.)
> Those people who think they know everything are a great annoyance to those of us who do.