George Berkeley

Bishop Berkeley subjectively thought
That objective existence is naught.
And he therefore conceived:
"That which is, is perceived."
Thus God's forming power is wrought.

George Berkeley (BARK-lee, 1685–1753) was an Irish philosopher who developed the theory now known as subjective idealism. He summed this up in his dictum, "Esse est percipi" ("To be is to be perceived"). In this he states that individuals can only directly know sensations and ideas of objects, not abstractions such as "matter". For the bishop, the sustaining power of subjective existence was evidence for God.