The Error of George Berkeley's Tree in the Park Argument
The so-called Tree in the Park Argument or Master Argument of the Irish philosopher, Bishop George Berkeley (1685-1753), has been analyzed and rejected by most philosophers, but it remains intriguing to many lay people. The following is Berkeley's presentation of the argument from his 1710 book, A Treatise Concerning the Principles of Human Knowledge. The conclusion of the argument is that there are no material substances, that is substances "existing unthought of or without the mind," and the argument is trying to prove that we can't even conceive of such things existing independent of mind. It is worthwhile for us who are studying things from a psychological angle to show the fallacy of his argument in a way that helps us remember the differences between imagination and perception and between the real and the unreal (and the ideal).
But, say you, surely there is nothing easier than for me to imagine trees, for instance, in a park, or books existing in a closet, and nobody by to perceive them. I answer, you may so, there is no difficulty in it; but what is all this, I beseech you, more than framing in your mind certain ideas which you call BOOKS and TREES, and the same time omitting to frame the idea of any one that may perceive them? 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 the objects of your thought may exist without the mind. To make out this, IT IS NECESSARY THAT YOU CONCEIVE THEM EXISTING UNCONCEIVED OR UNTHOUGHT OF, WHICH IS A MANIFEST REPUGNANCY. When we do our utmost to conceive the existence of external bodies, we are all the while only contemplating our own ideas. But the mind taking no notice of itself, is deluded to think it can and does conceive bodies existing unthought of or without the mind, though at the same time they are apprehended by or exist in itself. A little attention will discover to any one the truth and evidence of what is here said, and make it unnecessary to insist on any other proofs against the existence of material substance.George BerkeleyOf the Principles of Human Knowledge, Paragraph 23 — from the Project Gutenberg EBook — emphasis in text)
Berkeley's argument assumes the way we imagine trees in a park (for example) is to picture trees in our minds without picturing ourselves (we forget we are picturing, forget that we are imagining or conceiving).
But there are other ways to imagine or conceive of such trees which bypass Berkeley's method. Here is one:
For argument's sake, let's assume a man has access to a park or forest but has never gone into it and has never visualized any individual tree in it. Now imagine he goes into the park with a video camera and sets it up to start videoing at a later time in the day (or night), at a time when he will no longer be in the forest, and then to turn off by itself. (For my argument, it doesn't matter why he is doing this.) Imagine he makes a point of not noticing the area that will be videoed, and so he never sees any individual trees towards which his camera is aiming. If there are trees there, he doesn't care, and he doesn't even know it and isn't imagining any of them. (None of us have done any of this in reality; you and I, if you are following my thoughts, are imagining doing it. We may be imagining the trees in that man's forest, but the man we are imagining, if he existed, isn't imagining them).
Now the man leaves the forest and forgets about the whole project. The next day he goes and retrieves the camera, brings it home, and then looks at the video. He sees trees in the park (or forest). Perhaps he sees a squirrel running up and down one of them and maybe a fox going up to one and sniffing around its base. He never imagined any of this (nor did you and I), but it is there on his camera. It happened whether he imagined it or not (assuming the camera was working accurately). The camera is an object that doesn't imagine or conceive or perceive; it just films mechanically. So there was no imagining going on or conceiving or perceiving of what was going on, but something very definite and very real was going on.
It is necessary to add that what goes in in the world, the stuff that I am not aware of, that you are not aware of, that no one on earth is or ever will be aware of, can and does affect us all the time. These effects can be important and life shaping. A fox or squirrel running around in some forest may not affect us, but there are many things running around at this very moment that will — whether or not we imagine them or conceive of them.
This way of imagining the tree (and squirrel and fox) in the forest or park is a different way than the one used by Berkeley. Berkeley tries to get us to imagine a tree, and then he tries to get us to think that imagining, say with our eyes closed, is the same as perceiving with our eyes open. We all make this mistake when we "get lost" in our imagination. Then we get scared about something we think will happen or unrealistically happy about something that never has and never will happen. Berkeley tricks us into doing, pushes us into getting lost more than may be usual for us, through his use of reasoning.
Sensation types versus Imaginative types
Some people, by nature or by practice and self-control, would not be tempted to fall for Berkeley's thinking, because they are, what we call, "grounded" in everyday reality. Others don't mind drifting into their imaginations, into another world, and forgetting that it is their imaginations. There seem to be different psychological types. A person of one type may see no value in a person of the opposite type. A practical, down-to-earth person, (what Jung called a sensation type) will see the imaginative person (what Jung called the intuitive type) as a fool or, at best, a dreamer.
It is difficult to put into words exactly what a dreamer is. This is partly because the words we use depend, in part, on what type we are. But we can say that, for the dreamer, the line between imagining and non-imagining is often blurred. Projects come into mind already finished; the end is seen clearly and seems as good as done, and the idea that the steps could present insurmountable problems doesn't enter the mind. The idea of planning in a step by step way need not be done or should be left to "lesser" minds, according to the dreamer. The ideal is seen clearly, but the reality of trying to bring it into being and making it actual is barely considered if it is thought of at all. This leads to endless disappointments and torments when the dreamer runs into what others call "reality."
It is just a person who is under the sway of the imagination who would argue that nothing exists independent of our conceiving it, and this is one step from the common intuition or feeling or idea that if we want something enough of think positively about it enough, then it will happen.
It is very important to add that it is just this taking an outcome as real is what allows the dreamer-visionary to act at all. A more practical person who saw all the difficulties in advance, would calculate probabilities and never act. It is just the fact that the dreamer can't or doesn't see things in terms of probabilities that makes him (or her) dive in. And it is just this that leads to progress for the individual and also for humankind. That is to say, if the person survives. Even if the ideal or goal never is reached, any steps that have been made can be of benefit. Even if the dreamer haven't found a cure to cancer, they have learned to help many who suffer from the disease. I am tempted to say that, without dreamers there would be no progress, and also that any progress any of us makes is, because each of us, to some degree, is a dreamer. All goals, before they are reached are dreams; all theories, before they are tested, are dreams; and goals and theories that don't pan out, looking back on them, are just skeletons on the pile of yesterday's dreams.
Berkeley's psychological make-up
We can not be sure, since we did not know Berkeley, but I guess he was more of the imaginative type than the sensation type. It is true he must have had a powerful base in reality, since he became a Bishop and a Dean, but, at the very least, there was a strong pull towards the imagination, and we see this too in stories about him. (It is possible his pull to the imagination was a compensation for a very strong reality principle in him or that it was the fundamental principle of his nature and that staying in reality required a great deal of effort from him.)
Apparently Berkeley had a view that Europe was a civilization from the past and in decay and that the future of civilization would be in the West. He had an idea, perhaps a vision, that there should be a Christian college set up in Bermuda and that he would do it. He managed to get funding in England for the project, and he started to organize it, and then he left England for the New World to start setting up the college. A different kind of man would have waited until he actually received the funds, but he didn't; he left before the funds were actually issued. He must have thought it was a done deal which is quite unrealistic for anyone who knows how the world of finances work.
Berkeley never got further than Newport, Rhode Island, and he lived there for three years, before returning to England. The above group portrait was done by a Scottish painter named John Smibert who Berkeley, before leaving for America, invited to teach art at the hoped for college in Bermuda. The group portrait was completed by Smibert in London while Berkeley was still in Newport. I think the portrait of Berkeley (who is on the right) shows him as a dreamer/visionary type. (After Berkeley returned, Smibert moved to Boston and set up a studio there and became prominent.) (For more details about the Bermuda Group, the group advocating for a new college in Bermuda, please see the Yale Art Gallery catalogue entry.)
My picture is that, while Berkeley had a vision in his imagination of a new college and the good it would do, he misjudged the distance between the vision. It should be added that, though his vision never got translated into reality (at least by him), he did have an effect in the New World. For example, the future first president of King's College in New York (now Columbia University) was strongly influenced by Berkeley's philosophical thoughts.
Even if the reality of his ideas about the West were not made material by him, it seems they acted to inspire others. For example, the city of Berkeley in California was named after George Berkeley, apparently by men who were contemplating a line from one of his poems: "Westward the course of empire takes its way" (from a poem [which he, himself, called a "prophecy" in which the West is portrayed as the place in which the fifth, and apparently last act, of the "Drama" will take place).
There is a fine line between dream/prophecy/inspiration/imagination/vision and delusions. Towards the end of his life, Berkeley, who had returned to Ireland, turned to a different pass-time. In the 1740's there was a period of epidemics in Ireland. There were no medical doctors in Berkeley's diocese, and he began to mix his own medicine from pine tar oil and water. He seems to have believed in it and gave it for all illnesses. He wrote a poem to it that speaks of how the Lord, even though He is King of the universe, fills seemingly insignificant things with his power. It is on the most down-to-earth level that he works his wonders. (For a description of this period of his life along with a poem he wrote praising tar, I refer the reader to Berkeley's Life and Works.) I leave it to the reader to think about whether Berkeley's views on pine tar were visions or delusions and whether they were useful or harmful to him and others.