In my first essay I wrapped it up for life. Now, on to the meat.

You are reading this so I can assume you are at least something like me. Let's assume you can read; therefore we can assume you can see. You may be blind. If you are then let's assume you can hear or or at least feel, using your sense of touch. Seeing is a very rich sensation so it is easier to make my point, but what I am saying is still valid.

So let's assume you can see. Look around your room. Do it now, it only takes a second or two. Note the colours and shapes. See how things appear.

I'm trying to get you to notice what real philosophers call qualia.

Qualia are the qualities of experiences. Let's pin that down.

When you looked around your room, did you see anything that was red? I'm not trying to treat you like a child here. I'm trying to demonstrate something. I'm proving my point. Find something that's red.

Did you see it? So you know what's red. It's the colour of fresh blood, amongst other things.

Scientists describe colours as our interpretation of certain frequencies of electromagnetic radiation. Radiation is described as a wave. If you don't know what a wave is you need to go back to high school physics. A low frequency of light is red. A high frequency is violet. When electromagnetic radiation has a frequency below that of red light, it is called infra-red, literally below red. A frequency above that of violet light is called ultra-violet, literally above violet. You can buy ultra-violet (UV) lights, but you can't see the light that is emitted - our eyes aren't designed to respond to ultra-violet radiation. Similarily with infra-red (IR) radiation. You can buy IR-emitting electronic components, but you can't see the light they emit. In fact, IR is felt - as heat. Hot objects give of IR radiation.

Anyway, you might think that about wraps it up for colours. They are just frequencies of light. At the Stanford University Solar Center they explain why the Sun appears orange, in terms of frequencies of light. Georgia State University have a nice diagram. The physicists have it nailed down!

Wrong.

A frequency of light is a number. From that GSU page, visible light falls into the frequencies .003 - 4 x 10^14 Hz. Those are some pretty numbers.

In fact, .003x10^14 Hz is the frequency of light we perceive as the colour red.

Take a look at that red object you spotted earlier. Don't you agree? .003x10^14 Hz. I thought so too.

You should now understand that .003x10^14 hz is a frequency, and the colour of the red object is what you and I call red. You should also be able to see that that number says absolutely nothing about the colour red.

Redness is a qualium. It is what I call red and you call red. It's not that number, because that isn't red, it's just a number.

What I'm trying to get at here, in a clumsy fashion, is that awareness cannot be explained in terms of numbers, or frequencies, or mathematics. Awareness is that thing you have, that thing you are, that experiences red, as red, not as a number, but as red.

I should probably have chosen green, as my web page appears in green text on most browsers. Anyway, its too late. I chose red.

OK, I've defined qualia, I've shown you qualia, I've shown you that redness is a qualium and that, although things which give off electromagnetic radiation of the frequency .003x10^14 Hz appear red, .003x10^14 Hz is most emphatically not red.

I've explained that redness is something which awareness makes of that frequency of light.

If you're quick, I shouldn't have to go any further. Actually, if you're quick, you shouldn't need this explained to you. But let's continue.

Some people will argue, "No! Redness is what the brain makes of that frequency of light. There is no such thing as "awareness". These experiences are found in the brain. There are definite activities we can measure in the brain which corellate to the experience of redness. The seat of the mind is in the brain. Don't get so metaphysical!"

Those people are often very intelligent people. Their IQs are measured in numbers like 156. Mine is smaller. My IQ is probably something like 120; at least when I last measured my IQ, it was around 120. Above average, but by no means genius material. That's fine, I have logic on my side!

If the brain is the seat of the mind, and the brain is what perceives redness, then it is in the machinations of the brain that we should seek the experience of the colour red.

I used the word machinations deliberately. Biologists, neuro-biologists in fact, describe the brain as a system of organic components. They don't claim to understand the brain completely. They do claim to understand bits of it. I would say that yes, they do understand bits of it.

Let's examine how they understand the brain.

Like most scientists, they understand the brain as a system of interoperating parts. Those parts are brain cells, neurons. Neurons connect together in different ways and excite each other in different ways. Different patterns of excitation correspond to different input to the brain matter. When a light is shone into a subject's eyes, they can measure activity in the brain and pinpoint areas of the organ which are specialised in the perception of vision.

They describe the brain as a machine.

You put an input into the brain, and it responds in a particular way. Neuro-biologists are concerned with determining how the brain responds to different kinds of input. They hope, in this way, to build a model of the brain - a mathematical model.

This may be very useful. If the machinations of the brain can be modelled, then malfunctions of the brain may then be rectified! The neurobiologists are doing very good work.

When the biologists have a model which can predict brain activity given an arbitrary sensory input, they can safely claim to understand the brain.

Such a model reduces the brain to a machine. If the activity of the brain can be modelled then a machine can be built which will function in exactly the same way as the brain.

Some scientists claim that when this is done, the machine will perceive redness in the same way that you and I perceive redness.

At this point, the scientists must be declared to be insane; perhaps they can then use their model of the brain to remedy their own malfunctioning reason!

The question is, if we build a machine which reacts in the same way as our brain does to sensory input, does it perceive qualia?

A machine is a system of interoperating parts. The parts respond in a deterministic way to input. Let's imagine a machine that responds in a deterministic fashion to the colour red.

There would be a light sensor. It would detect light and pass a signal ".003x10^14 hz" into the brain system.

The system would react in a predetermined way to that signal. Let's say there's a buzzer that goes off when that signal is received.

Does the system experience the qualium of red?

Let's assume it does. Have a look at the red object you found earlier. How do you respond to it? Does a buzzer go off? Let's say the word "red" appears in your mind. You say "that's red" to yourself. Now, look at the object again, but this time, don't say "red". Say "blue". Is the object still red? Or has it changed to blue?

Mmmm. Still red?

The truth is that the signal we emit upon receiving the .003x10^1 Hz input is the qualia of the colour red. Not those words, but the redness itself.

A machine can't do that, because a machine doesn't know what red looks like. It doesn't have an awareness. It can't experience qualia.

The brain may be a machine, but if so it doesn't experience red.

The thing which experiences red is you, your awareness. And because you experience qualia, you are not a machine.

Awareness is a mystery unavailable to mechanical science. When a biologist says to you that the brain is a machine and there is no mind, just the brain, I hope you don't believe him.