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maxikov00

PA has a big advantage over object-level ethics: it never suggested things like "every tenth or so number should be considered impure and treated as zero in calculations", while object-level ethics did. The closes thing I can think of in mathematics, where everyone believed X, and then it turned out not X at all, was the idea that it's impossible to take every elementary integral algorithmically or prove that it's non-elementary. But even that was a within-system statement, not meta-statement, and it has an objective truth value. Systems as whole, however, don't necessarily have it. Thus, in ethics either individual humans or the society as whole need a mechanism for discarding ethical systems for good, which isn't that big of an issue for math. And the solution for this problem seems to be meta-ethics.

maxikov40

I agree with the first paragraph of the summary, but as for the second - my point is against turning applause lights for utilitarianism on the grounds of such occurrences, or on any grounds whatsoever. And I also observe that ethics haven't gone as far from Bentham as physics have gone from Newton, which I regard as meta-evidence that the existing models are probably insufficient at best.

maxikov00

Is this a bit Silicon Valley Culture? Because those guys do the same - they have a software idea and work on it individually or with 1-2 co-founders. Why? Why not start an open source project and invite contributors from Step 1? Why not throw half-made ideas out in the wild and encourage others to work on them to finish them?

For one thing, because open source community isn't terribly likely to embark on a random poster's new project, and you'll end up developing it mostly by yourself anyway. Furthermore, there's this aspect of hacker culture, and especially open source culture, where it's actively anti-evangelistic, and dislikes developing user-friendly things like Ubuntu, preferring Slackware or Gentoo.

maxikov50

That's actually surprising: I thought yeast survives freezing reasonably well, and http://www.ncbi.nlm.nih.gov/pmc/articles/PMC182733/?page=2 seems to confirm that. What was different in your setup so that even the control group had a very low survival rate?

maxikov100

Thanks so much for the detailed review and lots of useful reading!

maxikov00

Sure, I can easily imagine that by mentally substituting steel with jello - at some point you're tear it apart no matter how thick the walls are. However, that substitute also gives me the impression that most shapes we would normally consider for a vessel don't reach the maximum strength possible for the material.

maxikov20

Is that done to convert shear force to tension?

I wonder, how much can be achieved by merely increasing the thickness of the walls (even to such extremes as a small hole in a cubic meter of steel)?

maxikov10

Ah, that's true. I guess going back to normal vitals and motion is good enough for preliminary experiments, but of course once that step is over, it's crucial to start examining the effects of preservation on cognitive features of mammals.

Tardigrada and some insects are in fact known to survive ridiculously harsh conditions, freezing (combined with nearly complete dehydration) included. Thus, it makes sense to take a simple organism that isn't known to survive freezing, and make it survive. I suspect though that if you can prevent tardigrades from dehydrating before freezing, the control group won't survive, which means that some experiments can possibly be done on them too.

maxikov30

I'm sure I'm following why mammals should be less susceptible to this problem, can you elaborate?

Doing this with mammals has a lot of challenges though, which it'd make sense to bypass in initial experiments. The deepest dive (aside from humans in DSVs) is only 3km, which accounts for 30 MPa. I guess it's safe to say that no mammal can withstand 350 MPa with air or any gas in its lungs, so total liquid ventilation is required, which is just as challenging to do with sea mammals as with land mammals. Also, mammals are warm-blooded, and usually experience asystole at abnormally low body temperatures, which are nonetheless far above freezing. So there's the issue of making it survive the time it takes to go form cardiac arrest to freezing, which is also probably just as hard to do with sea mammals as with land mammals. So although the ultimate goal is to develop a protocol for humans, it'd the much easier to start with an animal that's already capable of surviving 100 MPa of ambient pressure and +4C of its own body temperature.

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