In his book Zarathustra, Nietzsche has his character Zarathustraboldly tell of a thawing wind which reveals that all is in flux:
“When the water hath planks, when gangways and railings o’erspan the stream, verily, he is not believed who then saith: “All is in flux.”
But even the simpletons contradict him. “What?” say the simpletons, “all in flux? Planks and railings are still OVER the stream!
“OVER the stream all is stable, all the values of things, the bridges and bearings, all ‘good’ and ‘evil’: these are all STABLE!”—
Cometh, however, the hard winter, the stream-tamer, then learn even the wittiest distrust, and verily, not only the simpletons then say: “Should not everything—STAND STILL?”
“Fundamentally standeth everything still”—that is an appropriate winter doctrine, good cheer for an unproductive period, a great comfort for winter-sleepers and fireside-loungers.
“Fundamentally standeth everything still”—: but CONTRARY thereto, preacheth the thawing wind!
The thawing wind, a bullock, which is no ploughing bullock—a furious bullock, a destroyer, which with angry horns breaketh the ice! The ice however—BREAKETH GANGWAYS!
O my brethren, is not everything AT PRESENT IN FLUX? Have not all railings and gangways fallen into the water? Who would still HOLD ON to “good” and “evil”?
“Woe to us! Hail to us! The thawing wind bloweth!”—Thus preach, my brethren, through all the streets!”
But those who think there are unchanging truths, especially truths about good and evil, may argue that it is Zarathustra (and most likely Nietzsche as well) who is the simpleton insofar as his own claim, “all is in flux,” would itself be in flux and thus not true since, while our estimations of the truth changes, the truth itself doesn’t change. To be sure, he cannot hold onto good and evil since he can’t possibly have any moral truth given his claims. But it turns out he cannot hold onto anything that would enable his brethren to “preach” a coherent message of the thawing winds of flux at all.