Physically, the body can shut down, with the lights shutting off one by one. Eventually, it'll break down, leaving behind minerals that will be scooped up and used for new life. Either your ash will become carbon for plants to use, or your decomposing body will leave behind nitrogen, potassium, and phosphate for plants to use. There has always been a beautiful, Buddhist like cycle of reincarnation there for me, because the minerals and molecules are passed from one organism to the next, then comes back around. That's the physical breakdown, and not what happens to your personal self, your laugh, smile, thoughts, and sense of style. And it doesn't touch on your final moments.
When I was a fan of drugs, I preferred the hallucinogenics. They can't stop time, but they can certainly slow your perception of time down to an eternity. Relativity is when your brain slows down to parade every insecurity you've had for you to see while you wonder if this parade of humiliation will last forever. The funny thing is about the break down of the basic mechanics of death, I failed to mention that in your final moments, your brain releases DMT. This is the stuff dreams are made of. Really, it's where dreams come from. Again with an anecdote, I have had a dream where I wake up in my bed, get dressed, walk out side, and the world becomes a wonderland. I can have a wild adventure while lying in my bed. Combine that with the brains ability to turn a few seconds into a few millennium, and there's my idea of the afterlife. How wonderful that few seconds will be will be based on my state of mind in my final moments, and a happy life will make a happy trip.
When a person dies they will leave something behind. Even the man who wanders the streets of St. Petersburg and only makes friends with the houses makes an impact on others lives. The reality of reality is, a person comes in to contact with others ever day and contributes something. This thing a person leaves behind, this is their chance at immortality. The people they affected carry with them memories, the work that they've done is their lasting impact on the world, and then there is the art and stories that they told. These pieces of them of them, the ideas of them, are just as alive as they are. It changes and grows as it gets passed from one person to the next, and from one generation to the other. This may be that soul thing I keep hearing so much about, a piece of me that has a chance of living forever.
With all of this in mind, why should death be left to chance? Why should suicide be a selfish act? Death will happen. You want numbers? According to this website, 62,000 deaths a year are from natural disasters. 13.3 million a year from communicable diseases. 3.3 million died between 1998 to 2002 in the war in republic of the Congo (so 660,000 a year, on average). There's a nice little chart on the website with all the probabilities on it, but it doesn't mention that the chance of dying is 100%. The rest is just a question of when and where it will happen. And when faced with that question of probability, we like to act like the man with a gambling addiction: well, I'm just lucky, therefore the worst won't happen to me. I deserve the best.
The question of suicide forces an interesting question onto one's mind. What have I put forth into this world? Wise men at their end know dark is right, and the idea of preparing for death is an old one; Pharaoh's could afford to build monuments to themselves, others buy plots of lands and write out their wills, and still others sit down to write their memories so they can be preserved. The question of "How do I want to die?" empowers the asker. It should be just as important of a question like marriage, children, and losing your virginity, and to that end it should be a question discussed with loved ones. It's a question that brings up interesting answers.
No life should be wasted. No matter what is done, Dylan Thomas and "Do not go gentle into that good night" should ring in your head like a theme song. How do you approach life though? Some wait for chances to come to them, others make sure that chances come to them. A third group ignores that, and just lives a life of experience and adventure, never bothered by the bigger questions because they are too busy with life. If given the choice of how to die, what would you choose? Letting life, or god, or chance and chaos decide allows an unfair fate become a person who has brought nothing but light to the world. It's natural, though, and it gives everyone around us the idea that we fought till the end. A nice romantic notion that we fought the god fight to the last breath, and showed death that life is worth fighting for. The decision of how you want to die is the guarantee you'll get that you will die with a piece of mind, surrounded by comfort and family. It's a decision of power, and gives the illiusion of control over the chaotic mess that is the world. And it is the reflection of a state of mind that shows that the person feels they have lived a wild and full life.
Personally, I hope it's over long before that for me. The question can be extended to "Well, what if I die tomorrow? What if I get into a car and a jaws of life takes me out? What if I just don't wake up? What if chaos wins? Can I be happy if with my life if this moment is my last?" Death is a final act, it can be a futile and meaningless event causing pain and bitterness for everyone. Death can be drenched in irony, and it can simply be fitting. I may not meet an end like Steve Irwin because my adventures are devoid of dangerous animals, but I hope that I live by Hunter S Thompson's words: "A day without fun is a day that eats shit." And I hope death can be a final decision made as a fitting bookend.