Is Reality All in the Mind?
All our experiences—all our perceptions, sensations, dreams, thoughts and feelings—are forms appearing in consciousness. It doesn't always seem that way. When I see a tree it seems as if I am seeing the tree directly. But science tells us something completely different is happening. Light entering the eye triggers chemical reactions in the retina, these produce electro-chemical impulses which travel along nerve fibers to the brain. The brain analyses the data it receives, and then creates its own picture of what is out there. I then have the experience of seeing a tree. But what I am actually experiencing is not the tree itself, only the image that appears in the mind. This is true of everything I experience. Everything we know, perceive, and imagine, every color, sound, sensation, every thought and every feeling, is a form appearing in the mind. It is all an in-forming of consciousness.
It is sometimes said that our image of reality is an illusion, but that is misleading. It may all be an appearance in the mind, but it is nonetheless real—the only reality we ever know. The illusion comes when we confuse the reality we experience with the physical reality, the thing-in-itself. The Vedantic philosophers of ancient India spoke of this confusion as maya. Often translated as "illusion" (a false perception of the world), maya is better interpreted as "delusion" (a false belief about the world). We suffer a delusion when we believe the images in our minds are the external world. We deceive ourselves when we think that the tree we see is the tree itself.
Although we may not know the external world directly, we can draw conclusions from our experience as to what it might be like. This, in essence, has been the focus of our scientific endeavors. But to our surprise, the world "out there" has turned out to be quite unlike our experience of it.
Consider our experience of the color green. In the physical world there is light of a certain frequency, but the light itself is not green. Nor are the electrical impulses that are transmitted from the eye to the brain. No color exists there. The green we see is a quality appearing in the mind in response to this frequency of light. It exists only as a subjective experience in the mind.
The same is true of sound. I hear the music of a violin, but the sound I hear is a quality appearing in the mind. There is no sound as such in the external world, just vibrating air molecules. The smell of a rose does not exist without an experiencing mind, just molecules of a certain shape.
The same is also true of the solidness we experience in matter. Our experience of the world is certainly one of solidness, so we assume that the "thing in itself" must be equally solid. For two thousand years it was believed that atoms were tiny solid balls—a model clearly drawn from everyday experience. Then, as physicists discovered that atoms were composed of more elementary, subatomic particles (electrons, protons, neutrons, and suchlike) the model shifted to one of a central nucleus surrounded by orbiting electrons—again, a model based on experience.
An atom may be small, a mere billionth of an inch across, but subatomic particles are a hundred thousand times smaller still. Imagine the nucleus of an atom magnified to the size of a golf ball. The whole atom would then be the size of a football stadium, and the electrons would be like peas flying round the stands. As the early twentieth-century British physicist Sir Arthur Eddington put it, "Matter is mostly ghostly empty space." To be more precise, it is 99.9999999% empty space.
With the development of quantum theory, physicists have found that even subatomic particles are far from solid. In fact, they are nothing like matter as we know it. They cannot be pinned down and measured precisely. Much of the time they seem more like waves than particles. They are like fuzzy clouds of potential existence, with no definite location. Whatever matter is, it has little, if any, substance.
Our notion of matter as a solid substance is, like the color green, a quality appearing in consciousness. It is a model of what is "out there", but as with almost every other model, quite unlike what is actually out there.