Hume's Influences

1. Hume's Influences
In a 1737 letter, Hume wrote that readers of the Treatise would benefit by looking at writings by Nicolas Malebranche, George Berkeley, Pierre Bayle, and René Descartes:

I shall submit all my Performances to your Examination, & to make you enter into them more easily, I desire of you, if you have Leizure, to read once over le Recherche de la Verité of Pere Malebranche, the Principles of Human Knowledge by Dr Berkeley, some of the more metaphysical Articles of Baile's Dictionary; such as those of Zeno, & Spinoza. Des-Cartes Meditations wou'd also be useful, but I don't know if you will find it easily among your Acquaintances. These Books will make you easily comprehend the metaphysical Parts of my Reasoning. And as to the rest, they have so little Dependence on on [sic] all former Systems of Philosophy, that your natural Good Sense will afford you Light enough to judge of their Force & Solidity. [Hume to Michael Ramsay, August 26, 1737]
Chronologically, the first philosopher on Hume's list is René Descartes (1596–1650). In his Meditations on the First Philosophy (1641), Descartes combats sceptics who doubt the existence of the external world and the reliability of our senses. To accomplish his task, Descartes himself provisionally plays the role of a sceptic and doubts everything that can possibly be doubted. Descartes then arrives at one absolute truth – his own existence – and uses this as a foundation for demonstrating all knowledge. Hume was probably influenced by Descartes's provisional doubting process, as Hume himself doubted the sources of human knowledge. Throughout Hume's philosophical writings, though, he also reacted against the more speculative metaphysical views that Descartes developed.
The remaining three philosophers listed in Hume's letter – Malebranche, Bayle, and Berkeley – were controversial figures when their writings first appeared, and they share the conviction that the true nature of the world is not as evident...