In “A Treatise Concerning the Principles of Human Knowledge” George Berkeley proposes one of the most outlandish and bizarre theories in the history of philosophy. And yet, more than three centuries later, although few support and try to defend, it remains an essential contribution to the philosophy of the Enlightenment. Boiled down to absolute basics, Berkeley outlines a proposed theory in the treatise which states that all matter exists only because it is perceived to exist.
This seems easy enough to disprove and many have taken great delight in doing: Samuel Johnson is said to have kicked a stone while observing that the very act was a refutation of Berkeley’s entire construct. The problem for Johnson and all other who leap to a quick dismissal of the idea that existence is dependent upon perception is that the treatise does not argue that a thing fails to exist because no one is there to perceive. That would be an argument like the famous query about a tree making a sound or not if no one is there to hear it. Berkeley’s theory postulates an acceptance that tree exists in a forest which even when no one is around to hear or see or touch or smell or whatever. An entire forest doesn’t disappear or get erased from existence merely because it isn’t perceived by anyone. That would be a kind of mad theory unlikely to seriously withstand the test of three months, much less three-hundred years.
Although many philosophical treatises were instigated as a response to a previous philosophical document, Berkeley’s response here is rather unique in that it has a specific motivation around which the idea developed and germinated. Although Berkeley was rather specifically responding to John Locke, ultimately his theory grew out of a fear of the Enlightenment as a whole. Berkeley was a clever man hardly deserving of the disrespect his admittedly eccentric theory brought him. He saw with a rare clarity the direction that the rationality and movement toward a mechanistic Newtonian view of the existence of mankind was heading and as a young man on his way toward becoming Bishop of Cloyne two decades later he did not like what he saw. The Enlightenment is now viewed as a kind of a scientific renaissance when outmoded concepts about god and religious beliefs were being transcended by rational scientific approaches. For deeply religious men—genuinely spiritual souls not in it for the corruption—like Berkeley, the Enlightenment could lead to just one ending: the rejected of organized religion and a massive embrace of atheism. So it was this fear of the collapse of Christianity which was the engine driving the composition of his treatise.
The thrust of that simplistic breaking down of the philosophical idea that all matter exists only because it is perceived rests upon the a crux that is not about whether something exists if it is not perceived, but everything clearly does exist, how is perceiving it. To go back to the tree and the forest where no one is around to determine whether the tree falling makes a sound: we all agree the tree and forest is still there, right? But if, as Berkeley argues, it can only be there if it is being perceived, then how is that possible? The answer, as the philosopher routinely pointed out, is so simple as to be impossible to deny. The forest can only still exist if no one is around to perceive it because it is being perceived by God. The very existence of anything that is not perceived by humans is therefore proof of the existence of God.
This theory has holes in it, of course, but Berkeley’s basic idea remains an essential one in the ongoing debate over the nature of perception and existence. That things do exist cannot be argued. That things which exist can only ever actually be proven to exist by being perceived is also true. The open question is that though we cannot actually something exists without perceiving it, we accept on faith that it exists. So where does faith in the untenable come from? So far, despite it being irrational, Berkeley has still provided the best answer to that question.
