Known sourcecanonical
"I do not know what I may appear to the world; but to myself I seem to have been only like a boy playing on the sea-shore, and diverting myself in now and then finding a smoother pebble or a prettier shell than ordinary, whilst the great ocean of truth lay all undiscovered before me."
Isaac Newton / Brewster's Memoirs of Newton. Vol. ii. Chap. xxvii.
Brewster's Memoirs of Newton. Vol. ii. Chap. xxvii.
Bartlett's Familiar Quotations, 9th ed. (Little, Brown, 1905), public domain