I need you to tell me what’s wrong with the line of reasoning I’ll describe below. I’m embarrassed that I can’t figure it out myself. It’s not a trick. I’m genuinely curious where my blind spot is.
The argument I’ll describe isn’t new. I’ve written on this topic before, just for fun. But I don’t recall seeing anyone explain why it’s wrong. I’ll number the assumptions and components so you can more easily tell me where the reasoning is broken.
1. If humanity survives long enough, our technology will reach the point where we can send an unmanned rocket to a distant planet that we deduce has a reasonable chance of sustaining life.
2. By the time we can do such a thing, hundreds or even thousands of years from now, the cost of each space flight will be far more affordable than now.
3. Private organizations could have the resources to send such rockets, so there might be a wide variety of reasons to do so, including religious, scientific, and philosophical motives.
4. One of those reasons could be to “seed” other planets with the building blocks of life as found on Earth. The impulse to do this will seem greater if life on Earth is threatened with an impending natural disaster.
5. We humans often perceive that the end of the world is near. If it isn’t a meteor, or nuclear war, or climate change, or super virus, it’s something new. We’re good at feeling doomed.
6. Those unmanned space flights might take millions of years apiece, but unless a rocket strikes something in the vast emptiness of space, it can be built to survive the trip.
7. The rockets will contain the basic building blocks of life, and by then we will have the knowhow to store those ingredients without the risk of degrading.
8. Future humans will assume that evolution will do its thing on the new planet and create a wide variety of life. And there would be a strong possibility that in at least one of the seeded planets some version of intelligent life, much like us, would evolve.
9. Future humans will know that they need to send many rockets toward many planets if their goal is to successfully seed at least one with life.
10. When the intelligent life on those other planets evolves to the same level of technology as the civilization that created them, they are likely to repeat the cycle, sending out their own rockets to seed yet more planets with their own building blocks of life.
11. If all of these steps are likely to happen in the future, there is a strong chance it has already happened, and we are an intermediate step and not the ones who will someday go first.
12. Considering all of these assumptions and likelihoods, we are more likely than not a result of an alien seeding operation.
One argument against this line of thinking is that we won’t ever have the technology, resources, or desire to seed other planets. But I think all of those things are likely unless technological and financial progress ends within the next thousand years. I’m optimistic that humans can last at least that long.
Another argument against this line of thinking is that life might happen routinely whenever a planet with water and chemical diversity is a certain distance from its sun. Therefore, no seeding is needed. But assuming we can’t know that for sure at the time we send out the seed ships, given that the distances will make direct observations impossible, that could mean that some number of planets have both naturally occurring and seeded forms of life at the same time.
Where is the argument broken?