Thomas De Quincey

No man ever will unfold the capacities of his own intellect who does not at least chequer his life with solitude.

Thomas De Quincey, ‘Suspiria de profundis: Being a Sequel to the Confessions of an English Opium-Eater’, Blackwood’s Magazine, vol. 57, no. 353 (March, 1845), p. 270