The reality we see exists only in our minds

"If a tree falls in a forest and no one is around to hear it, does it make a sound?" Only a small percentage of the population actually understands this philosophical question. It has nothing to do with animals. The question is whether sound waves and sounds are the same thing or whether the sounds we perceive are merely contingent on sound waves. The fact is that unless a sound wave is detected by a sentient creature which can perceive it, it makes no sound. For example, a dog whistle can be heard by animals but to a human it makes no sound. This is because our ears can't detect sounds of such a high frequency. Dogs hear the sound, but we don't. If nothing detects the sound waves, no sound is heard. So to answer the question, "If a tree falls in a forest and no one is around to hear it, does it make a sound?", the answer is a resounding no! In pitch darkness we see nothing. Does this mean reality ceases to exist if there is no light? Or does it just mean that our image of reality can't exist without light? I should actually thank Con for stating that the image we see is contingent on reality. By doing so he admits that what we "see as reality" and "actual reality" are two separate thing. What we see may be a very accurate depiction of reality which is why humans are the dominant species on the planet, but it is not reality. It is merely a 3 dimensional visual representation of reality, created by our minds from input received from our senses and enhanced by our brains. Because this image of reality is the only one we can experience it is very hard for most people to understand that is is merely a sensation. It looks real and feels real. But pain also feels real. Yet pain does not exist outside of our perceptions. Happiness, sadness, love, anger are other examples of things we feel but which do not exist outside of our perceptions. They may be the result of things that happen in reality, but they do not exist in reality. To answer your questions: Pro, would you agree that we can detect the visible light spectrum? yes. Does the visible light spectrum only exist in our minds? no Is the visible light spectrum part of reality? yes But the visible light spectrum consists of rays with different wavelengths which our minds interpret as colors. Wavelengths exist in reality, colors do not. Please note, i am not saying, nor have i ever claimed that colors are imaginary. They are the result of light waves striking our eyes. They would not be created without light. But the colors exist only in our mind. Light itself has no color. Con seems to be arguing that for something to exists only in the mind must be totally independent of reality. http://www.ghc.org... How Our Bodies Turn Food Into Energy All parts of the body (muscles, brain, heart, and liver) need energy to work. This energy comes from the food we eat. Our bodies digest the food we eat by mixing it with fluids (acids and enzymes) in the stomach. When the stomach digests food, the carbohydrate (sugars and starches) in the food breaks down into another type of sugar, called glucose. The stomach and small intestines absorb the glucose and then release it into the bloodstream. Once in the bloodstream, glucose can be used immediately for energy or stored in our bodies, to be used later. As we can see, the glucose is created by our bodies by breaking down the carbohydrates we eat. Our brains work the same way. It takes raw data from "external reality" and creates images, colors, sounds, smells and tastes. These things are contingents on "external reality" but do not exist in "external reality".