Pickwick is in Dickens’s career the mere mass of light before the creation of sun or moon. It is the splendid, shapeless substance of which all his stars were ultimately made. You might split up Pickwick into innumerable novels as you could split up that primeval light into innumerable solar systems. The Pickwick Papers constitute first and foremost a kind of wild promise, a pre-natal vision of all the children of Dickens. ... Dickens, like every other honest and effective writer, came at last to some degree of care and self-restraint. He learned how to make his dramatis personæ assist his drama; he learned how to write stories which were full of rambling and perversity, but which were stories. But before he wrote a single real story, he had a kind of vision. It was a vision of the Dickens world—a maze of white roads, a map full of fantastic towns, thundering coaches, clamorous market-places, uproarious inns, strange and swaggering figures. That vision was Pickwick.
G.K. Chesterton, Appreciations and Criticisms
of the Works of Charles Dickens