Berkeley’s critique of the calculus is a well-known topic, as are his attempts to build a brand-new geometry based on sensible minima, but the notion of a Berkeleian mathematical philosophy has hardly been examined. Some recent works have nevertheless tried to analyze what this philosophy could be.

For the last 30 years I have been writing a trilogy on Locke’s, Berkeley’s, and Hume’s philosophies of money. With the publication of Clipped Coins. Abused Words and Civil Government; John Locke’s Philosophy of Money and Exciting the Industry of Mankind; George Berkeley’s Philosophy of Money and with the last volume on Hume in preparation, the trilogy is now almost completed.

In this paper, I would like to show how it is possible to understand and comment on Berkeley’s Siris. This book is not that difficult nor that obscure. Siris is unusual: Berkeley seems to have or to invent a new philosophical style. However, firstly, it is still philosophy; and, secondly, it is necessary to stress that, unlike his first works, Siris was read everywhere in Europe.