One difference is the time frame involved. The Fermi Paradox remains very robust because we can view galaxies from Andromeda, which is only a few million light-years away, to the Hubble Ultra Deep Field, which has galaxies billions of light-years away (and therefore viewed billions of years in the past). We have an entire spectrum of time presented to us thanks to varying distances, and we see no evidence of intelligent life anywhere we look.
And near-light travel could settle whole portions of the sky in mere eyeblinks by comparison to how long galaxies exist. Sitting around on an island for 30 to 100 years doesn’t compare.
Another difference is the fact that the humans already had a functioning civilization somewhere, and traveled to that island, which would be analogous to humans settling other parts of the galaxy rather than being stuck on a single planet where we still are. The islanders are already past the filter point.
The two situations aren’t identical, they just have some similarities when it comes to applying anthropic reasoning. The filter in James’ example can be in two possible places: getting to the island, or surviving on the island. These are analogous to the filter being during the rise of civilization and being during civilization surviving long enough to colonize the galaxy.
Why aren’t the filters during the rise of intelligent life and during intelligent life surviving long enough to settle the islands?
The entire point of the analogy, as far as I can tell, is to move to a domain where our intuition works better. We don’t have strong intuition about time frames and probabilities involving the rise of intelligent life. We do have intuition about tribes exploring and colonizing islands. We don’t have strong intuition about how long it takes for intelligent life to reach the point where they can settle islands. We do have intuition about the likelihood of natural disasters wiping out island tribes.
It’s a matter of time scales and probabilities. Robin Hanson’s filter involves astronomical time scales and difficult to measure probabilities. James presents an example with human time scales and probabilities that are relatively easy to measure. The point is not to capture the physical acts (colonizing the stars), but to capture the anthropic reasoning and conclusions.
We do have intuition about tribes exploring and colonizing islands. … We do have intuition about the likelihood of natural disasters wiping out island tribes.
I don’t. I have no idea what the success rates of prehistoric humans settling large islands was.
I don’t have specifics either, but I do have some intuition. I know about volcanic islands. I know about volcanic eruptions in recent history. I know about past cities destroyed by volcanoes. I have some idea about how far into the ocean tribal-level technology can take you. I have some idea as to how fast people tend to spread out and explore in general.
We’re not trying to narrow our confidence intervals on a cosmic filter by equating it to an island filter. Rather, using anthropic reasoning seems sketchy, so we seek out other problems using anthropic reasoning to see if the anthropic principle holds up. It’s the anthropic principle itself we’re analyzing here, hence the title of the post, “An empirical test of anthropic principle.”
I don’t think this analogy maps very well.
One difference is the time frame involved. The Fermi Paradox remains very robust because we can view galaxies from Andromeda, which is only a few million light-years away, to the Hubble Ultra Deep Field, which has galaxies billions of light-years away (and therefore viewed billions of years in the past). We have an entire spectrum of time presented to us thanks to varying distances, and we see no evidence of intelligent life anywhere we look.
And near-light travel could settle whole portions of the sky in mere eyeblinks by comparison to how long galaxies exist. Sitting around on an island for 30 to 100 years doesn’t compare.
Another difference is the fact that the humans already had a functioning civilization somewhere, and traveled to that island, which would be analogous to humans settling other parts of the galaxy rather than being stuck on a single planet where we still are. The islanders are already past the filter point.
The two situations aren’t identical, they just have some similarities when it comes to applying anthropic reasoning. The filter in James’ example can be in two possible places: getting to the island, or surviving on the island. These are analogous to the filter being during the rise of civilization and being during civilization surviving long enough to colonize the galaxy.
Where to place the filter for a proper analogy doesn’t seem as clear cut to me.
Why aren’t the filters during the rise of intelligent life and during intelligent life surviving long enough to settle the islands?
The entire point of the analogy, as far as I can tell, is to move to a domain where our intuition works better. We don’t have strong intuition about time frames and probabilities involving the rise of intelligent life. We do have intuition about tribes exploring and colonizing islands. We don’t have strong intuition about how long it takes for intelligent life to reach the point where they can settle islands. We do have intuition about the likelihood of natural disasters wiping out island tribes.
It’s a matter of time scales and probabilities. Robin Hanson’s filter involves astronomical time scales and difficult to measure probabilities. James presents an example with human time scales and probabilities that are relatively easy to measure. The point is not to capture the physical acts (colonizing the stars), but to capture the anthropic reasoning and conclusions.
I don’t. I have no idea what the success rates of prehistoric humans settling large islands was.
I don’t have specifics either, but I do have some intuition. I know about volcanic islands. I know about volcanic eruptions in recent history. I know about past cities destroyed by volcanoes. I have some idea about how far into the ocean tribal-level technology can take you. I have some idea as to how fast people tend to spread out and explore in general.
I prefer to leave my confidence intervals very wide (+/-100%) than to inappropriately reduce the problem to one where “our intuition works better.”
I guess I don’t like anthropic reasoning in general.
We’re not trying to narrow our confidence intervals on a cosmic filter by equating it to an island filter. Rather, using anthropic reasoning seems sketchy, so we seek out other problems using anthropic reasoning to see if the anthropic principle holds up. It’s the anthropic principle itself we’re analyzing here, hence the title of the post, “An empirical test of anthropic principle.”
Yes, that is exactly what I want to do.