Descartes' Dream

These hands; I'm watching them hop up and down on the keyboard. They seem real to me; that is, I believe in them and rely on them and would feel sorely unfortunate if I found that they had left me. I see them in my dreams as well. In my deepest sleep they appear before me, much as they are now, and I believe in them during this time. Upon waking, however, I see that they have, in fact, been snuggled under covers for hours, and not actually holding the reins of a rainbow horse. I am tricked over and over, every night. The dream world seems as real as waking life, until it's over--though I imagine the same thing can be said of waking life.
How do I know what's happening in my dream? I see it. I feel it. I hear it and sometimes I even taste and smell it. I use what I might call my senses to perceive it. And yet my senses deceive me, for surely I wake to a lack of evidence of that dream life, just as much as I come into that dream world to find no evidence of what we call "awake".
I rely on my senses to navigate me through this life. If my senses can be so misled, to think I am walking across a tundra holding a chickadee when in fact I lie here breathing, then everything-- I mean everything-- can be called into doubt. We think what we see and perceive is true, but is it only really true in our minds? Rene Descartes wondered about this over four hundred years ago. He said, "it is a mark of prudence never to trust wholly in those things which have once deceived us" (Descartes 13). How can we ever trust our senses again after such shenanigans as dreaming?!
As far as my consciousness goes, Descartes never existed at all. I know he did because I've been told, and I've read his work and seen drawings of his face. I have never encountered him with my own senses, but am compelled to disregard his absence in my perceptions. My senses are useless in proving the existence of Descartes, and thus my senses are not comprehensive.
Things are not always as they appear to be. This is a universal human idea that manifests in religion and spirituality, but how far can this idea be taken? It does seem unlikely that there is nothing outside of mind, but things, as I have said, are not always what they seem. When I put a paintbrush into a jar of water, though I believe in its essential straightness and solidity, it appears to be broken and the top half is levitating on the surface of the water while the bottom half, magnified, rests not unusually on the bottom.
What about real things that are perceived only by myself? Pain, for example, exists urgently in my shin right now, as I tripped up the stairs in the dark a few moments ago. I think it's real, but I cannot see it, touch it, or express it to anyone else accurately. Where is the pain anyway? I may think it's in my leg, but science has explained that electric signals make their way to my brain where they are decoded and register somehow as a very negative perception. The pain exists only in my mind, and if that weren't there, there would be no perception, whereas if my body didn't exist, but only my mind, I might still know pain because that is its true residence.
Descartes also discusses the fallibility of perception when it comes to insane people. I think his discourse is quite humorous. "Insane people. . . continually insist that they are kings when they are in utter poverty, or that they are wearing purple robes when they are naked, or that they have a head made of clay, or that they are gourds, or that they are made of glass". I believe in his concluding statement in this paragraph: "But they are all demented, and I would appear no less demented if I were to take their conduct as a model for myself"(Descartes 14). In other words, he cannot assume that he is sane and grounded in reality enough to draw valid conclusions when this is exactly the same reasoning and feeling that the insane have when they assert that they are gourds. Crazy people have the same amount of, and sometimes more, conviction in that which we see as their delusions.
Our minds, Descartes relates, are much more clearly and distinctly known to us than our bodies are. The concept of the evil genius allows him to disregard the world outside of his mind without the bias religious idea that a supremely good god created all that appears before him. He supposes that everything he perceives is the malicious trick of an evil genius. This part of his argument seems half baked in that he is recognizing personified evil and good. He just couldn't quite dismiss god, so he made an equal opposition to be the devil's advocate. Things are not as they seem, however, and I will take his word for it for the purposes of this argument. All things come into question except the fact that I think therefore I am. Cogito ergo sum. Whether or not anything exists is up for debate, but the fact that I am thinking, reasons Descartes, this, and this alone, not even the evil genius can negate.
The very fact that we can use this world to our advantage is incredible. This is a waking dream over which we have every power. The rules-- laws, physics, structure-- are superfluous and the only real rebellion is the individual taking place in the higher reaches of the mind.
How can we assume that our perceptions are so rock solid that we may use them as the foundation for all other knowledge? An illusive posteriori supposition is not an honorable foundation to stand on, and yet so many minds go through their whole lives blindly building up, at best, a house of cards.