The life we lead is based on assumptions. To change your life there needs to be a questioning of these assumptions.

Assumption One: What your senses tell you is true

This is one of the easiest assumptions to question then demolish! You have five senses: sight, hearing, touch, smell and taste.

Let’s image that you are sitting on a riverbank. What do you see?

Outside of yourself you see all the elements that make up the scene: the river, a fisherman, mountains, trees and so on.

But is this really what is going on? Light waves from the river, the boat, the mountains, the trees and all the other components of the scene travel at a speed of 299,792,458 metres per second. They then hit the photoreceptor neurones in the retina of your eyes. These then generate electrical impulses that go to the brain which then processes these impulses and creates the scene which you are viewing. If you then move your head then the brain has to update these images. If the fisherman moves his boat then more updating has to take place. To you this all appears seamless with no apparent ‘break’ in the action. This is because he brain updates the images so rapidly that you do not notice any breaks. It is similar to how you watch a film. A film is a series of still images flashed one after the other onto a screen at a speed of about 25 frames a second. You do not notice each still image. If the film is say, a boat crossing a river, then the illusion is created of continuous movement.

Are you seeing everything as it is in the present moment? The light from near objects reaches your eyes before the light from distant objects. At a speed of 299,792,458 metres a second the light from the mountains and the river get to your eyes very, very fast. This means that for most practical purposes this is not a problem. If you are playing tennis, for example, the time that the light from the ball takes to reach your eyes and then the time for the image to be processed by the brain and updated rapidly, followed by the time it takes for your brain to tell your arm to move is so fast that it does not prevent you from hitting the ball with your racket if you are a good tennis player. So, the illusion is created that everything is taking place in real time, when you can only ever deal with the past when it comes to vision.

If you move to a much wider scale - say when you look at the sky, then the stars that you see are so far away that the light can take years to reach your eye. Star distances are often measured in light years. A light year is equals 5.88 million million miles. This is how far light travels in one year at a speed of 186,282 miles per second or 299,792,458 metres per second. The star nearest our sun is Proxima Centauri which is 4.3 light-years from the Sun. The Sun is 93 million miles from the earth. This means that we can only see a star as it appeared at least 4.3 years ago. At these distances we are literally viewing the past.

The other illusion is that you are looking at something ‘out there’. In reality, because it is the brain creating the images, all is happening inside your brain. There is no ‘out there’ at all. Even the fisherman is perceived inside your brain. Even though you may put your hand out and feel the cold of the river, you still can only see the river from inside your head.

Another strange effect to notice is that when our retina receives the light, the image that is formed is upside down. Our brain corrects this so that everything appears the right way up.

The sound that reaches your ears travels at 770 miles per hour, which is considerably slower than the speed of light. This means that, if the fisherman is singing, then the image of his mouth moving reaches you much faster than the sound. This effect can be noticed if you are a few hundred yards away from the start of an athletic race that is started by a starting pistol. As the gun is fired you see the smoke arise from the barrel before you hear the sound of the gun firing. The speed of sound can also vary according to temperature and the altitude. The higher and colder the air is, then the slower sound travels. The medium in which sound travels also affects its speed - whether this be water or glass for example.

You put your hand into the river. How long does it take for you to feel the river? As you touch the river, impulses travel through the nerve network in your body to your brain. Normally the rate at which these impulses travel is about 331 metres per second. This is a bit slower than the speed of sound at around 346 metres per second at 82 degrees Fahrenheit.

What at first appears to us as a simple situation - sitting on a river bank, seeing a scene, being aware of the smells, touching the water, thinking about what you are seeing, is an extremely complex mechanism. Energy in the form of light is being received by your retina, sound waves reach your ear drums, odour molecules reach your nose, nerve impulses enter your brain, electrical impulses occur in your brain that we call thinking. All these different forms of energy travel at different speeds - yet we view it all as if it takes place in the now or the present. It is our mind that processes all this information to create what appears to be ‘reality’ - yet the way we comprehend all this is an illusion created by us to make sense of it all. Indeed we must make sense of it all, otherwise it would be impossible to live in this physical world. We need to be able to walk, avoiding objects, react to the sound of a roaring lion so that we can take flight before it pounces and eats us.

It is our brain that makes sense of everything we see - but can we trust our own brain?