Planetary Comparison

I should be doing homework, and I need something to get my brain out of the mud. So I'm going to spend the next few minutes writing about aliens.

Yes, I know. They seem unlikely. They've been romanticized, feared, and whatever else. They've been the stars of countless movies and books, and I think that's why many people are so reluctant to believe in them.
But they're almost certainly there.
Just think of our solar system, with nine planets. Okay, so Earth has life, but it had to happen somewhere, right?
Now, if you're not thinking in the correct perspective, I suppose you could be right, if you say that it happening in only one place is plausible.
But look at it this way: Our solar system. Nine (or eight, I suppose) planets. Each of these planets has several satellites, or moons. That's quite a lot of rock and gas. We, on Earth, have life. Many scientists suspect Mars used to have life, or even that there could be some extremely resilient microscopic organists still managing to survive. Just look at the extreme conditions some Earthbound organisms can survive--I mean, poisonous, boiling water, buried miles underground with no sunlight, and still surviving? And not just that, but thriving?
That's just mental.
And many scientists suspect that there could be life under the vast ice sheets of Europa, one of Jupiter's moons. It's not just a crazy few scientists, either--a very, very large number think that it's certainly plausible.
Feel free to quote me. My source is National Geographic.

And besides our sun, with Mars and Europa, there are over one billion (1,000,000,000) stars in our galaxy, many of which have their own planets. Have you ever tried counting to a billion, one unit at a time? I have. Have you ever succeeded? I certainly haven't.
And then there are countless other galaxies. Probably trillions. Just go look at one of Hubble's famous space photos, one of those with so many galaxies within that it's almost impossible to count. In the distance, you can see faint glowing which indicates countless more.
All of that, from a section of space as small as if you made a small cylinder with a circumference of about 1 cm (maybe even smaller), held it up to your eye, and looked at the sky.
So how are you going to tell me there's no other planet with life?