George Berkeley, later known as Bishop Berkeley was on March 3, 1685, at Dysert Castle in County Kilkenny, Ireland.

He was an Anglo-Irish thinker and Anglican bishop with a devout belief in himself as English, and a great deal of thought and publication on original philosophical views.

Berkeley travelled to England in 1713. He was an intellectual and social success in London; he met the essayists Joseph Addison and Richard Steele and later contributed articles to the Guardian. He became, in short, a respected thinker of his time.

One of his greatest unique-for-the-time philosophical views, that pertains to modern virtual reality as much as it did his world, was the materialism of objects.

In Essay towards a New Theory of Vision he argued that man does not immediately perceive either the distance of objects from him or their spatial relations to others. He states that distance and magnitude are suggested by past experience of the correlation between sight and touch.

In other words, Berkeley's position was thus: There are minds, souls if you prefer, in existence. There are also sensations, and ideas, also in existence. The two form a kind of cosmic scale, with the minds on one end, and the sensations on the other, feeding into the minds.

The former are selves, like you and me, and the latter are the entities known by selves-the so-called objects of knowledge.

In this way, all the objects in the world around us, are not actually physically there. Instead, they are just ideas, concepts, that our minds process as being there, from the output the sensations produce. Now, this is actually a very advanced concept, and one that modern neuroprosthetics is only just finding out - the physical object does not have to be there; if you can reproduce the sensation from the nerves, you reproduce the belief in the object.

Berkeley meant it as a manifestation of God's will creating the world -as ideas in God's mind. However, modern-day efforts on VR can and do, make use of the same argument to postulate that there may be fundamentally no difference between so-called physical objects, and the ones created by simulation - both are simply experienced as sensory impulses to the brain.

According to Berkeley, it was a short step for him from the psychological recognition of the ideality of sense perceptions to the metaphysical acknowledgement of the immateriality of all reality.

He was the first thinker to take the position of denying material reality. In Principles of Human Knowledge (written in 1710) and Three Dialogues Between Hylas and Philonous (written in 1713) he argued that if the only evidence for an object's existence is its being perceived, then the conclusion is that existence consists entirely in being perceived or perceiving and that minds and their ideas constitute reality.

For Berkeley the fundamental question was what is it we actually mean we say that something "exists"?

His analysis from multiple vectors, looks at the question from almost every conceivable angle, and he concludes that all we can possibly mean when we say that a thing exists is that the thing is being perceived. To exist, and to be perceived, for Berkeley come down to the same thing. To be means to be perceived, or esse est percipi, Berkeley's famous principle.

Berkeley retired to Oxford University in 1752 and died suddenly on Jan. 14, 1753, aged 67.

References

George Berkeley: Information from Answers.com
http://www.answers.com/topic/george-berkeley

Wikipedia entry on George Berkeley
http://en.wikipedia.org/wiki/George_Berkeley

Introduction to Philosophy: Bishop George Berkeley
http://home.myuw.net/tkerns/MyUWsite/
waol-phi-website/lecsite/lec-berke.html