David Hume (1711–1776) was a Scottish philosopher and the third man in the troika of British Empiricists. He was influenced by and expanded upon the ideas of John Locke and George Berkeley. Hume not only denied the existence of the material substances of Locke, but also the spiritual world of ideas proposed by Berkeley. Hume also rejected the existence of the individual self. You do not exist. According to Hume, you are nothing more than what he called “a collection of different perceptions.” He dismisses the scientific principle of cause and effect and states that knowledge of anything as certainty is just plain impossible, except maybe mathematics.

Hume explained his position as follows: “Reason can never show us the connexion of one object with another, tho' aided by experience, and the observation of their conjunction in all past instances. When the mind, therefore, passes from the idea or impression of one object to the idea or belief of another, it is not determined by reason, but by certain principles, which associate together the ideas of these objects and unite them in the imagination.”

Being obliged to at least pretend he existed in the real world, Hume wrote extensively about economics as well as philosophy. He also wrote a highly regarded history of England that looks at historical events from an economic perspective.