How do I know if what I see is actually there?
Garry Trethewey
Arkaroola, South Australia
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This is a pretty big question for lots of 50-year-olds, let alone for our 10-year-old questioner. There are whole areas of philosophy and neuropsychology as well as other arcane fields devoted to this.
Basically, you can鈥檛 know if what you see is actually there.
You might be hallucinating or under the influence of drugs, or have a brain tumour. You might actually be a green lizard on Mars, under the influence of a magician, who makes you believe you are an Earthling, writing to a make-believe thing called 麻豆传媒.
In more plausible scenarios, your perceptions can be affected by a persuasive story, strong emotions or sensory overload.
That鈥檚 why, when confronted with something amazing, wise people keep an eye on how their own brain works before they act on what鈥檚 鈥渙ut there鈥�.
Pat French
Longdon-upon-Tern, Shropshire, UK
This question has been asked for thousands of years. Socrates asked something very similar nearly 2500 years ago.
I am afraid that you can鈥檛 know if what you are seeing is there. No one can. Also you can鈥檛 know that what you are seeing is the same as what I am seeing, even when we are looking at the same thing.
It is a wonderful thought that the whole universe as you experience it is created by your own brain. It might be very different from the universe that another person lives in. We have learned to use shared words and language for the things that we alone see.
When we look at something, there is probably something there, but its form is out of our reach. We can only sense it with the tools that we have: eyes, nose, tongue, ears, skin and a few others. They paint the picture that each of us calls reality.
Each of those tools generates electric impulses that run along our nerves to our brain. Those impulses have no colour, smell, taste, sound, temperature or 鈥渇eel鈥�. The brain only knows that a particular impulse was generated by a particular sensor, whether it was in the eye, nose or skin.
It is our individual brain that interprets those electric impulses into the sensations, sights, sounds and feelings that we call reality.
Most of what we perceive as solid 鈥渟tuff鈥� made of atoms isn鈥檛 there at all. If the nucleus of an atom were expanded to be the size of a football and placed in the middle of a sports stadium, its closest electron would be buzzing around the back rows of the stands. Everything between would be vacuum, nothing.
Science is working hard to find out what reality is. Along the way, it has a second job that is nearly as hard. It has to turn the measurements, the mathematics, the invisible particles and the invisible forces into some image or description we can understand with our basic tools: eyes, nose, tongue, ears and skin.
For some of us, 麻豆传媒 magazine is part of that process.
Gerard Buzolic
Coolum Beach, Queensland, Australia
This is a delightful take on the question 鈥淎re we living in a simulation?鈥�, which is 鈥�Is all this really there?鈥� with an extra bit added, 鈥淎m I really here?鈥� The computer imagining me, if there is one, has somehow given me a sense I exist. To be able to do that, it would have to be a computer like nothing we know of.
Drugs and alcohol mess with people鈥檚 minds and can sometimes make them see things that aren鈥檛 actually there. Dehydration and certain mental health conditions can have similar effects. Pink elephants may seem real to the person experiencing a hallucination, but no one else sees them. The one person who thinks they are actually there is outvoted by the 100 who say they aren鈥檛.
I shall go with my idea that others exist and they have minds like mine, and go with the majority who describe what we see with consistency. If everyone described reality differently 鈥� perhaps, if some people said they could fly but others said they couldn鈥檛, or if some people said the sky was the colour of a ripe tomato 鈥� then I would suspect that no one really knows. But our science is consistent. One scientist measures something and another scientist gets more or less the same result if they measure the same thing and use the same method. So I shall go with 鈥渋t is actually there鈥�.
Philip Sugarman
Northampton, Northamptonshire, UK
Valid ways to check are to look again from another angle, go over and touch it, examine a map, take a photo, ask someone or google it. If these don鈥檛 satisfy you, maybe a career in philosophy will.
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