George Berkeley
George Berkeley (Bark'-lee) (1685-1753) was an influential Irish philosopher whose primary philosophical achievement is the advancement of what has come to be called subjective idealism, summed up in his catchphrase, "To be is to be perceived." He wrote a number of works, the most widely-read of which are his Treatise Concerning the Principles of Human Knowledge (1710) and Three Dialogues between Hylas and Philonous (1713) (Philonous, the "lover of the mind," representing Berkeley himself).
Though born in Ireland, Berkeley was very much an American philosopher. While it was in Ireland that Berkeley had his initial insights into the ideality of the objects of perception, his greatest philosophic insights and the most important projects of his life aimed at applying his principles (including his project to found a utopian society in Bermuda and his medical enterprises) began only with his trip to America.
As a young man, Berkeley demonstrates that the objects we perceive exist precisely as they appear to the senses. Objective knowledge is possible because the perceived object is the only object that exists. There is no "real" object which is the substratum of the perceived object. There is no physical or material object existing so to speak "behind" the perceived object. There is no "real" object "behind" the object as we perceive it, which "causes" our perceptions. All that exists is the object as we perceive it, and this is the real object.
Since the object we perceive is the only object that exists, the object is precisely as it appears and, if we need to speak at all of the "real" or "material" object (the latter in particular being a confused term which Berkeley sought to dispose of), it is this perceived object to which all such names should exclusively refer.
It follows that: (1) Our perceptions of objects are all perfectly accurate and objective; (2) Any knowledge of the empirical world is to be obtained only through direct perception. (3) Error comes about through thinking about what we perceive. (4) Knowledge of the empirical world of people and things and actions around us may be purified and perfected merely by stripping away all thought (and with it language) from our pure perceptions.
From this it follows that: (1) The ideal form of scientific knowledge is to be obtained by pursuing pure de-intellectualized perceptions; (2)If we would pursue these, we would be able to obtain the deepest insights into the natural world and the world of human thought and action which is available to man. (3) The goal of all science, therefore, is to de-intellectualize or de-conceptualize, and thereby purify, our perceptions.
This is the essence and starting point of Berkeley's basic philosophy. Unfortunately, this doctrine is completely ignored by virtually all scholars today since there is not one who actually takes Berkeley seriously in the sense of approving of his precise philosophical principles as forming a legitimate method for pursuing scientific knowledge.
Yet without a firm grasp of these principles, it is impossible to render an accurate account of Berkeley's ideas or successfully apply them in any scientific enterprise.
The philosophy of David Hume concerning causality and objectivity is an elaboration of one aspect of Berkeley's philosophy. Immanuel Kant mischaracterized Berkeley as a radical idealist and falsely claimed that Berkeley's principles make objective knowledge impossible. As Berkeley's thought progressed, he more or less completely assimilated his theories to those of Plato. The only modern philosophers who adequately appreciated and applied Berkeley's principles were Hume and Arthur Schopenhauer.
Discussion (to be rendered into tighter prose?):
You see a redwood tree. Ha! It's only there while you're looking at it. It was only an image in the mind of God, which the Almighty let you hallucinate on.
In response to the old riddle, "If a tree falls in the forest and no one heard it, did it make a sound?," Berkeley would reply that if no one were there, the tree wouldn't be there.
This is eerily similar to recent theoretical physics notion that mass does not exist.
As Bob Dylan sang about dreams, "It's all in your head."
For detailed replies to all questions submitted by students and scholars seriously interested in the philosophy of George Berkeley visit: http://www.georgeberkeley.org/
For a list of the published works by and about Berkeley as well as Berkeley links: http://georgeberkeley.org/_wsn/page2.html