The probability that the universe contains life is probably high, the only way to confirm it is to actually see other life, until then there is only wild speculation. There is in fact a formula, but no values to put into it.
Number of galaxies * avg number of solar systems per galaxy * what percentage of solar systems contain planets * what percantage of planets lie within the habitable range * chance of habitable planets bearing life ... it is perfectly correct in math, but we have no concrete data for which to use it. Although the first 2 values reach further than we might think, the others are a lot less than we think at the moment. But every time we see a solar system with a planet the chances of life in the universe go up.
As for the size of the universe:http://en.wikipedia.org/wiki/Hubble_Deep_Field, empty space... yeah right.
Mars is smaller than the earth, this means that it will have caused less volcanic activity in its creation, yet still retianed its atmosphere for a while. This was before the earth's volcanic period ended. Mars has in fact had a longer time than the earth to "create life". Mars has almost certainly had oceans, long before the earth had. It is from a mathematical point, more likely that mars would evolve life than the earth. Isn't that somehting to think about?
But Mars became cold, and eventually lonely, since it couldn't retain its magnetic field which kept away the solar winds. The atmosphere was literally blown away. Mars's life simply died. The interesting thing to note is that the Earth had most likely cooled by this time. And some bacteria can survive space travel and plenty of heat. So it is possible that an asteroid of some proportion hit Mars and sent a piece of Mars flying inwards, onto earth. And if it landed in an ocean, the heat would not be great enough to obliterate the projectile... It is perfectly possible life originated from Mars. We could very well be the martians, invading earth.
About humans being violence loving idiots who would any day destroy themselves... is just not what I think. We are not inherently violent, less in fact than most animals able to do violence. Few other animals obey without fighting first, and no animals show compassion and mercy the way we do. We are not more violent, we are just better at doing damage. If every cat was able to fire off nukes, would there be a terror balance or a world devastation?
Another light on this matter is as some have partly said, genetic drive, or "darwinism" if it clarifies. Our sniper rifles are just advanced ways to compete for the resources. Every animals fight in one way or another for food, space, hierarchy, and/or females. If a life arrived in a world where resources were infinite, and competition was non-existent, they would in fact have little reason or genetic drive for intelligence. In a way, violence is required for sentience to be achieved.
If we meet aliens, it is very likely they are equally violent, or perhaps even more violent than us, rather than being the all-knowing pacifists some would believe.
Regarding conspiracies, I like south park's the most.
The conspiracy is a conspiracy since the government want the people to think they have the power. It is in fact the government who runs all the conspiracy sites...
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