Glanvill's first work (a passage in which suggested the theme of Matthew Arnold's Scholar Gipsy), The Vanity of Dogmatizing, or Confidence in Opinions, manifested in a Discourse of the shortness and uncertainty of our Knowledge, and its Causes, with Reflexions on Peripateticism, and an Apology for Philosophy (1661), is interesting as showing one special direction in which the new method of the Cartesian philosophy might be developed.
He studied philosophy at Athens under various teachers, notably Antiochus of Ascalon, founder of the Old Academy, a combination of Stoicism, Platonism and Peripateticism.
The admixture of Stoic elements is so great that some critics have attributed the work to a Stoic author; but the writer's Peripateticism seems to be the more fundamental constituent of his doctrine.
He assails them on twenty points of their mixed physical and metaphysical peripateticism, from the statement of which, in spite of his pretended scepticism, we can deduce some very positive metaphysical opinions of his own.
On the other hand, he came to represent those aspects of Peripateticism most alien to the spirit of Christendom; and the deeply religious Moslem gave his name to the anti-sacerdotal party, to the materialists, sceptics and atheists, who defied or undermined the dominant beliefs of the church.