Buffett said, if there is a significant drop, remember:

In the letter to shareholders written in 2017, Buffett stated: "No one can predict how deep stocks will fall in the short term." But he said, if a significant drop does happen, "please remember these lines from Rudyard Kipling's classic poem 'If' written in 1895":

"If you can keep your head when all about you are losing theirs...

If you can wait and not be tired by waiting...

If you can think and not be ruled by your thinking...

If you can trust yourself when all men doubt you...

Yours is the Earth and everything that’s in it."