After reading this post, I would like you to understand that everything you experience is 'within' your consciousness, and what this entails. That's my aim, anyway.
You accept that the [physical] screen you're looking at isn't in your head and yet you are aware of it. Furthermore, you could tell me the shapes and colours of its components and how it feels to the touch. If it burst into flames you could exclaim: 'it smelt horrible!' and could also let me know what it tasted like, if you really wanted. Is there a monitor really there? If it is, does it really have these properties? Do I experience the monitor in the same way you do?
It's important to note at this point any assumptions I will be making so that you are aware of the limitations of my suggestions. The first assumption I will make is that there is a physical reality and we're not all just brains in vats nor that, for example, there is only consciousness. The second assumption is that consciousness is in some way related to the brain.
There are various other views out there. Take a look at this lecture by Peter Russell and this lecture by Thomas Campbell for some interesting and well presented differing and opposing views to my own. They're quite long, so you'll have to set aside time for them.
So, baring these assumptions in mind, let's examine the experience of looking at an object. Science tells us that before you see the object light travels from it to your eyes where it is focused onto your retina. Here chemical reactions occur to produce electrical pulses that correlate to the intensity of the light at each receptive cell. These pulses are sent, via the optic nerve, to your brain. It is here that things get a little fuzzy. Continuing my physical explanation, I could tell you that neurons fire and synapses spark, but not that you see the object. Yet you do!
No field of science - nor anything at all - understands or explains this phenomenon, hence why I describe it as "fuzzy". So what do we know? Well, although there is disagreement, I would say it's near certain that something in your brain either is the experience of 'seeing' or causes it. If consciousness was unrelated to the brain, how would it be explained that human consciousness is limited to only the inputs (senses and bodily information such as sight, how hot you are and things like headaches) the human brain receives and things it can come up with on its own (memory, dreams etc.)? Further, when conscious decisions take place the body is controlled by sending signals via the nerves from the brain; if consciousness is not related to the brain why would this be the case? Unfortunately, that's about all: we know so much about the brain, but not about its link with consciousness.
It follows that as experience is either consciousness itself or is a consequence of consciousness we can't claim that two people experience the same thing as we don't understand consciousness. Say the object you are looking at is red, if I look too will I see the same colour? If for both of us 'red' makes us happy for some reason, is my feeling of happiness the same as yours?
This leads to an important problem concerning consciousness and the brain. If my experience is the same as yours, as everyone's, why should this be? And if not, why not?
Consciousness provides you with an interpretation of the physical world as well as a window onto a number of other functions of the brain such as memory and the ability to control your breathing. Colour is not the property of an object but the frequencies of light it absorbs and reflects are. You see red but the object isn't fundamentally red; red is your interpretation. This is the same for all your senses, all your experiences. Be careful not to misconstrue this as "red isn't red" or, considering the sense of touch, "cold isn't cold". Something cold is cold (i.e. it has less heat energy than something warm) but it itself does not have the property of the feeling of cold. The feeling of cold is your interpretation or understanding of the physical property, its heat energy.
If you have accepted that consciousness is related to the brain you will also accept that it is therefore only possible to experience, be conscious of, inputs and internally generated information such as memories or thoughts. That our experience is limited by these features entails that it would be possible to experience other things, given more inputs. No one can possibly imagine what these would be like, but we do know that other animals have different or enhanced senses from our own. Dogs have an increased sense of hearing and smell, some creatures 'see' ultraviolet light and single cell creatures experience nothing at all.
Hopefully, by now I have achieved my goal. If successful I have shown you that your experience is somehow linked with your brain and that what you experience is not the world but an interpretation of it limited by your senses and brain wiring. I have more thoughts on this and will expand and extend at a later stage. First though, it's important to understand what I have presented here.
