"Another acquaintance he made in Paris [in 1792] was John Stewart, an eccentric figure known as 'Walking Stewart.'"

"His nickname came from the fact that he had walked halfway round the world, from Madras, through Persia, Arabia, Abyssinia, much of North Africa, and every country in Europe as far as Russia. He refused to take carriages because they were both elitist and cruel to horses. He came to believe that there was an impending 'universal empire of revolutionary police terror' that would 'bestialize the human species and desolate the earth.' The police state would ban his books, so he urged readers to translate them into Latin (a precaution against the supposed decay of the English language) and bury them seven feet underground. Their locations would be passed down orally until the dawn of the age of the Stewartian man made their disinterment possible. Despite these bizarre beliefs, Thomas De Quincey, who wrote a wonderful essay about him, said that his political views ‘seemed to Mr Wordsworth and myself every way worthy of a philosopher.'"

From "Radical Wordsworth: The Poet Who Changed the World" (commission earned). 

Here's De Quincey's "wonderful essay." Two sentences from it: "On the whole, if Walking Stewart were at all crazy, he was so in a way which did not affect his natural genius and eloquence--but rather exalted them. The old maxim, indeed, that 'Great wits to madness sure are near allied,' the maxim of Dryden and the popular maxim, I have heard disputed by Mr. Coleridge and Mr. Wordsworth, who maintain that mad people are the dullest and most wearisome of all people."