Consciousness Exists

I have often heard people (especially, computer scientists) say "consciousness does not exist". This is, quite literally, the stupidest thing one could try to argue.

The fact is that consciousness is the only thing you experience directly. Hence, its existence is the only thing you can know for sure. Everything else -- the universe, people, atoms -- is conjecture.

Don't get me wrong: I'm quite convinced that the universe is real. But consciousness is the foundation, that through which you experience and gain knowledge of the world. You cannot distrust consciousness without distrusting everything.