The aliens among us

Of course, the case against alien visitation remains strong. On its side is common sense, the absence of anything close to knockdown evidence, the general notion that very large changes in our understanding of the world are rare, and the observation that if advanced aliens somehow were here, they either would be entirely hidden or much more obvious.

Still, when you run all the arguments through your mind, is it not possible to come away with an estimate of at least a one-in-a-thousand chance that alien visitations are a real thing? Even such a small chance would be worthy of more discussion. And might I be able to talk a few of the bolder ones among us up to a one-in-a-hundred chance?

Regardless of how you judge the likelihood, you can still benefit from thinking more deeply about the mysteries of the universe and our place in it. Perhaps the earth has life because it came from other solar systems, seeded by alien probes, and indeed that is what I would do if I were a very wealthy alien philanthropist. If you end up with 100 successfully seeded solar systems for each very advanced civilization, the resulting odds suggest that we are indeed the result of a seed.