What is the Nature of Reality? Berkeley's Inconceivability Argument

Berkeley's Inconceivability Argument: Why Bodies are Nothing More than Perception

It is one of the most basic human intuitions that the bodies we encounter in our everyday experience exist are physical bodies-- that is, they are composed of physical particles that we can see and touch and smell, and that these qualities, irrespective of our sensing them, exist in the bodies themselves. For example, if I were to stand up from the chair I am sitting in and leave the room, I intuitively believe that the chair is still sitting in the same place, undisturbed. Therefore, if humans and other sentient beings were wiped off the face of the earth, the non-sentient bodies-- like chairs and trees and tables-- will continue to exist. Bishop George Berkeley seeks to turn us away from our basic intuitions, and persuade us that bodies as we commonly think of them are no more than our perceptions of them. Their supposed physical "particles" are mere perceptions, and they do not exist outside of our own mind. This results in a world of "immaterialism", a world in which to exist means to be perceived by a perceiver, rather than being composed of physical parts that exist as things in themselves. One of Berkeley's arguments against our basic intuitions is a simple challenge: Try to conceive of a body existing independent of anybody perceiving it. Berkeley finds this challenge is impossible, and thus is confident that his "Master Argument" has proven immaterialism once and for all. However, when we further investigate the premises of Berkeley's argument, we find that some premises are open to objection.

The force of Berkeley's argument from inconceivability rests in the contradiction that results from conceiving of a body existing independently of the mind. Intuitively, we might think it quite simple to conceive, for example, that the room we are sitting in now will still exist once we leave the room. In fact, we are quite inclined to believe that it exists as a thing in itself; that is, it's existence is not dependent upon anyone's perceiving it at all. However, Berkeley sees a contradiction in such an exercise. He writes,

" But do not you yourself perceive or think of them all the while? This, therefore, is nothing to the purpose; it only shows you have the power of imagining or forming ideas in your mind, but it does not show that you can conceive it possible that the objects of your thought may exist without the mind." (POHK23, 475)

The inconceivability argument is built on three premises: First, for a body to be mind-independent, it must be able to exist without anybody perceiving it; that is, it would exist as a thing in itself. Second, when we think of such a body in our minds, we are perceiving it all the while. Third, if we are thinking and perceiving of the body all the while, then it is not existing independent of our conceiving or thinking it. Therefore, we cannot think of such an body existing unthought of. Therefore, the existence of mind-independent bodies is impossible.

In this argument, there are two premises in particular that are vulnerable to objection. First, Berkeley seems to confuse the terms conceive and perceive with regards to the argument. For example, he says, "To make this out [conceiving of a mind-independent body], it is necessary that you conceive them existing unconceived or unthought of, which is a manifest repugnance" (POHK23, 475). However, let us consider his second premise, "But do not you yourself perceive or think of them all the while?" In this case, Berkeley seems to be using the two terms, conceive and perceive interchangeably-- to think of an object. But to conceive a body is to frame an idea-- for example, I can conceive the idea of a unicorn in my mind. To perceive an body is to come to the idea of it through direct, immediate sensory experiences-- for example, I perceive the tree standing right in front of me. I can conceive a unicorn, but strictly speaking, I cannot perceive it. My sensory experience with this tree is vivid and immediate; on the other hand, my conception of a unicorn seems to be distant and mediate. Therefore, in the strictest sense, if we are conceiving of a mind-independent object, we are not necessarily perceiving it all the while.

If we try to conceive an unconceived object, once we conceive the object in our mind, it ceases to be unconceived and thus results in a contradiction. Berkeley is certainly correct on this account. Now the question becomes: Can we conceive (that is, think it to be possible) a body, at any particular moment, being unperceived (that is, not being subject to the immediate sensory experience of a perceiver)? This more specific question is more likely what Berkeley was attempting to answer. Certainly, as Rene Descartes and others argue, we cannot possibly conceive of something entirely unperceived, or of a completely new nature (Meditation I, 28). Berkeley says, "... I have a faculty of imagining, or representing to myself the ideas of those particular things I have perceived and of variously compounding and dividing them"(POHK10, 464). All of our conceptions are merely amalgamations of previously perceived perceptions. Applying that reasoning to this case, any attempt to conceive of a mind-independent body is merely conceiving of a body resembling perceptions of a body I had perceived before. For example, the reason I believe can conceive of a tree existing in a forest without my perceiving it is because I had previously stood in the forest and perceived it before. If a body existing "unperceived" in this case means never having been perceived before, then the argument from inconceivability maintains its force. However, if we take it to mean being unperceived at any particular moment in time, then Berkeley has to show us more to turn us away from our basic intuitions about bodies. For example, it seems quite simple to conceive of my philosophy classroom while I am not sitting in it, and the representation will bear striking similarity to my immediate perception of it while I am sitting in it. Berkeley calls this mere "imagining". However, isn't this mere "imagining" something possible grounds for "conceiving" something as possible? Berkeley seems to make a distinction in the argument between "imagining" something and "conceiving" that something as possible. If he is to be committed to this distinction, then he must further show why "imagining" and "conceiving" are two different operations of the mind.

Second, there is a hidden premise in the argument from inconceivability, namely that what is inconceivable is impossible. Berkeley is very assertive in the claim that not only do mind-independent bodies not exist, but that their existence implies a contradiction and thus their existence is impossible. He writes,

" ... So it is impossible for me to see or feel anything without an actual sensation of that thing, so it is impossible for me to conceive in my thoughts any sensible thing or object distinct from the ,sensation or perception of it. In truth, the object and the sensation are the same thing and cannot therefore be abstracted from one another." (POHK5, 471)

However, there have been many instances throughout history in which previously "inconceivable" concepts indeed turned out not only to be possible, but to be actualized. It was inconceivable for most until the 16th century that the earth would revolve around the sun, and not the other way around. It was inconceivable until the 19th century that there could be any non-Euclidean geometry. It was inconceivable that cars, or televisions, or computers could exist until much recently. Berkeley might respond to this objection by maintaining that these concepts weren't really inconceivable at all-- merely, they were believed to be inconceivable because they were beyond the progress of human understanding. That certainly is a legitimate argument, but isn't it also possible that his thought experiment is merely beyond the progress of human understanding, and might eventually be solved?

Thankfully, through the wonders of modern technology, there is such a way to answer Berkeley's challenge. Suppose, for example, that I am standing in a forest perceiving a tree. Berkeley challenges me to prove that this tree will still exist when I leave the forest and am no longer perceiving it. To meet his challenge, I set up a camcorder on a tripod. I leave the forest for 2 hours. Two hours later, I return to the forest and retrieve the camcorder. When I play back the tape, sure enough that same tree I formerly perceived was still there during the time when I was not present to perceive it. Thus, Berkeley's argument seems to be refuted.

Berkeley may raise some objections to my claim of victory. One objection he might raise is that the camcorder is itself a perceiver, and thus the tree is still being perceived in some sense. To assert this, however, is to assert that the camcorder is a spirit with the capacity for perceiving bodies, which is patently nonsense. Second, he may maintain that the tree continues to exist because there still is a perceiver present--- God. Berkeley's deus ex machina solves all the problems of unperceived bodies, because by God's continual perceiving of these bodies, they maintain a continual existence. Thus it is not the case, as it seems, that bodies pop in and out of existence as we humans perceive or unperceive them; no matter where we are, God is always perceiving these bodies. Even so, Berkeley does not seem to find any inherent problem in the notion that bodies go through rapidly succeeding stages of existence and non-existence because he has re-defined what it means to exist.

The argument from God's perception, however, raises another aspect to our original question, "Do mind-independent bodies exist?" Berkeley maintains they can't, but even if we as humans aren't perceiving them, they continue to exist due to God's perceiving them. However, Berkley also maintains that there is a numerical and qualitative distinction between our ideas and God's, and furthermore, our ideas and everyone else's. God, as an infinite and eternal being, must perceive all bodies eternally, and, furthermore, must perceive all possible bodies. From our experience, we know that bodies typically are finite in their existence, and we know that we don't perceive all possible bodies. So, to account for this, Berkeley must explain how and why God's perceptions become perceptible to us, and how and why they become imperceptible to us. What causes such a transformation?

There are two possible answers to this question: One, assuming God's perceptual ability is a passive one like ours, then it is the perceptions themselves that cause their transformation. However, this would result in a contradiction--- if these perceptions are able to transform themselves, without the aid of God or humans, wouldn't they be mind-independent bodies? Berkeley, therefore, must not accept this claim. The second possible answer is that God, rather than being a passive perceiver, wills these perceptions to become perceptible to humans. But this answer seems to implicate that these willed "perceptions" are very similar to what we would consider "things-in themselves". Certainly, owing to Berkeley's earlier claim, they cannot exist unperceived, because of God. But is that the sense in which we want to define mind-independent bodies? Certainly, along the same lines, a theistic materialist can argue that material bodies are willed by God. What makes it more likely that God would will mere perceptions rather than material bodies? What is the significant difference between, say, a body-in-itself, relative to human understanding, and a perception of God? It would seem most theistic materialists are willing to admit that what they perceive as "things-in-themselves" are dependent on God. The sense in which most want to define "things-in-themselves" are bodies that can exist independent of human perception. By making the claim that even if existence is not dependent on the human mind it always depends on some mind (God), Berkeley does not seem to advance the discussion of the nature of bodies.

A third objection raises questions about God as a perceiver. If God's perceiving bodies allows them to exist, then what perceives God? If Berkeley is to stay committed to his thesis that mind-independent bodies do not exist, God cannot possibly exist as a body in and of itself. There must be a perceiver that allows God's existence, and a perceiver to perceive that perceiver, and so on ad infinitum. Berkeley may answer that God, as an infinite being, perceives himself. But it seems that something that perceives itself is quite independent. To assert that God's existence is dependent upon his perceiving his self is begging the question. It fallaciously assumes that there is a God perceiver already existing, in order to prove the claim that God exists.

In conclusion, Berkley's argument from inconceivability must be stronger on two counts: One, he would need to demonstrate that what is inconceivable is impossible, which is perhaps the most important premise in his argument. Second, he would need to formulate an objection to the camcorder argument-- if we can plainly demonstrate that a tree existed in the forest in a timeframe whilst no one was there to perceive it, he must prove that what we are now perceiving as a "tree" on the camcorder is not what we think it is; or, if he acknowledges its existence, he must demonstrate how God's ideas, though fundamentally different from ours, still allow us to perceive the tree in a similar manner as we did before. His argument for God as an infinite perceiver is also vulnerable, as it falls to the same line of objection as the First Cause argument. The argument from inconceivability is certainly a novel argument, but it does not seem to withstand the rigors of careful inquiry.