George Berkeley

George Berkeley (IPA: /ˈbɑː(ɹ).kli/, Bark-Lee) (12 March 1685 – 14 January 1753), also known as Bishop Berkeley, was an influential Irish philosopher whose primary philosophical achievement is the advancement of a theory he called "immaterialism" (later referred to as "subjective idealism" by others). This theory, summed up in his dictum, "Esse est percipi" ("To be is to be perceived"), contends that individuals can only directly know sensations and ideas of objects, not abstractions such as "matter.