Bishop George Berkeley

The philosophical ideas of Bishop George Berkeley (1685-1783) are ones which are terribly difficult to explain to non-philosophers without evoking any eye-rolls. The question of whether a tree falling in the forest with nobody present makes a sound or not is typically seen as a perfect example of how philosophers contribute nothing at all to human well-being. It will be the purpose of this post, however, I will attempt to show that not only does Berkeley’s philosophy give us more than a merely trivial thought experiment, but that the falling-tree story is not even a very accurate description of the absolute idealism which Berkeley advocates.

As we saw earlier, it is less than perfectly clear whether Locke was a materialist like Hobbes or a dualist like Descartes, although most today probably go with the former. Another feature of Locke’s philosophy which became very widespread was the idea that the human mind, upon birth, is a tabula rasa, a blank slate, and that nothing could be in the intellect which was not first in the senses. Thus, for Locke, all contents of consciousness are either ideas, or correlated combinations of such, these ideas being perceptions of either primary qualities (mass, hardness, etc.) or secondary qualities (color, taste, smell, etc.). What Berkeley did was take Locke’s strong empiricism (nothing is in the intellect…) and argue that such a position undermines both the distinction between primary and secondary qualities as well as the materialist position altogether.

Let’s begin with Berkeley’s treatment of Locke’s metaphysics. Locke rejected any kind of realism as it relates to universals as advocated by Plato. Instead, he favored a conceptualist view of universals, or nominal essences, wherein abstract notions such as justice, good, beauty, etc. are not real entities in some hidden realm, but are instead simply abstract concepts. Berkeley, however, thought that such a view was entirely incompatible with Locke’s empiricism, for ideas can only be of particulars, never of anything abstract. According to Berkeley, there is no such thing as an idea or mental picture of something abstracted away from all particular features.

Accordingly, there is no such thing, as far as we can ever possibly tell by way of experience, as a primary quality of an object, for it is impossible for us to gain perceptual knowledge of something which has not been perceived. Berkeley goes even further, for matter itself is simply a primary quality, and as such we have absolutely no acquaintance with it. Of course we have ideas of matter, but we are only acquainted with these ideas, not with matter itself, and accordingly that there is matter at all is simply a superstitious, metaphysical dogma. Indeed, following Ockham’s razor, it is not merely the case that we need not believe in matters independent existence, but rather that we should not believe in it.

We are thus left with absolute idealism, in which nothing exists which is not perceived. Berkeley illustrates this doctrine by arguing that for a thing to exist, it must have attributes of one form or another. Consequently, for an attribute to exist, it must be perceived, and perception entails a percipient. Thus, Esse Est Percipi, to be is to be perceived.

From these conclusions, Berkeley moves on to defending religion against what he sees as the attack of mechanistic materialism. For starters, we have no reason to believe that there is matter in the world, and accordingly all objects are instead ideas in the world. Consequently, only minds, which are themselves composed of ideas, are capable of producing or causing ideas. But while we are capable of producing ideas by way of imagination and reflection (Locke certainly allowed for this) we are not capable ourselves of producing ideas by way of sensory perception. Perceptual ideas must originate from another mind, and this mind is God. Thus, the dark side of the moon, although nobody in Berkeley’s time had yet seen it, did in fact exist in his time since this idea was in God’s mind.

Thus we can see what Berkeley’s ideas suggest about that darn tree in the forest. There is no such thing as a tree in the forest with nobody around, for God is always there. Accordingly, it always makes a sound. If NOBODY were around, then not only would there be no sound, but there would be no tree and no forest either. Indeed, according to Berkeley, the law-like behavior of the universe is no due to matter’s properties, for there is no such thing as matter, but is instead due to God’s mind and will. (We simply must admit that on this point his explanation does seem more satisfying.)

There is a now famous limerick which addresses Berkeley’s doctrine quite nicely:

There once was a man who said, ‘God
Must think it exceedingly odd
If He finds that this tree
Continues to be
When there’s no one about in the Quad.’

A reply:

Dear Sir, Your astonishment’s odd:
I am always about in the Quad;
And that’s why this tree
Will continue to be,
Since observed by Yours faithfully, God.

Of course Berkeley’s idealism sounds patently absurd to our ears today, but it should be noted that he felt himself to be arguing for common sense. While objections can be raised to his account, (for instance why is the positing the existence of God’s mind any less of a violation of Ockham’s razor than the existence of matter?) it should be noted that his arguments do make for an effective argumentum absurdum against any strong form of empiricism.