Benjamin Graham on market timing

Yet we can not avoid the conclusion that the most generally accepted principle of timing is that purchases should be made only after an upswing has announced itself, is basically opposed to the essential nature of investment.  Traditionally the investor has been the man with patience and the courage of his convictions who would buy when the harried or disheartened speculator was selling.  If the investor is now to hold back until the market itself encourages him, how will he distinguish himself from the speculator and wherein will he deserve any better than the ordinary speculator's fate?

~ Benjamin Graham, Security Analysis, p. 15

(As cited by Dan Ferris, Stansberry Investor Hour, 11:30 mark, January 21, 2021.)