I've been thinking a lot recently about antidepressants and the human brain (not that I'm an doctor or anything) and it occured to me that if mood is nothing more than a balance (or imbalance) of chemicals in the brain, surely this must mean that everything we know, feel, think and experience is nothing more than the interactions of chemicals in the brain?

If we can regulate mood with drugs, then the next natural conclusion is surely that every feeling, thought, memory, emotion and idea you and everryone else has ever had is nothing more than a bunch of chemicals interacting inside your skull, the random firing of a few neurons pusling with electricicy?

Call me old-fashioned, but I find that incredibly depressing. What this must logically mean is that there is no "us" at all, that our consciousness is nothing more than an illusion, a succession of electrical impulses and chemical reactions? No soul, not even any real mind to speak of, because if all that is required for consciousness is a small ball of electricity and liquids, then our minds must be nothing more than hightly complex machines. Also, where does this leave free will? If everything we think, feel and do is governed by physical interactions of substances in our brains, then do we even have any say in what we think/feel/do, or are we just slaves to the chemicals?

I can imagine a grim Matrix-like future where nobody does anything anymore, and instead just hook themselves up to big machines to give themselves artificial experiences by manipulating brain chemistry.

What do you think? Apologies if this has depressed anyone, but I've been obsessed with this kind of thinking recently (a symptom of my possible depression, I suppose). Any thoughts (assuming thought exists, that is)?