Problem with playing russian roulette under those circumstances is that you might suffer debilitating but technically nonfatal brain damage.
Yes, that was acknowledged as the limiting factor. However it is not a significant problem when playing a few of rounds of Russian Roulette. In fact, even assuming you play the Roulette to the death with two different people in sequence you still only create two bits of selection pressure towards the incapacitation. You can more than offset this comparatively trivial amount of increased injured-not-dead risk (relative to the average Russian Roulette player) by buying hollow point rounds for the gun and researching optimal form for suicide-by-handgun.
The point is, yes exploiting death-immunity for optimization other outcomes increases the risk of injury in the same proportion that the probability of the desired outcome is increased but this doesn't become a significant factor for something as trivial as a moderate foray into Russian Roulette. It would definitely become a factor if you started trying to brute force 512 bit encryption with a death machine. That is, you would still end up with practically 0 chance of brute forcing the encryption and your expected outcome would come down to whether it is more likely for the machine to not work at all or for it to merely incapacitate you.
This is a situation where you really do have to shut up and multiply. If you try to push the anti-death too far you will just end up with (otherwise) low probability likely undesirable outcomes occurring. On the other hand if you completely ignore the influence of "death" outcomes being magically redacted from the set of possible outcomes you will definitely make incorrect expected utility calculations when deciding what is best to do. This is particularly the case given that there is a strict upper bound on how bad a "horrific incapacitation" can be. ie. It could hurt a bit for a few hours till your certain death.
This scenario is very different and far safer than many other "exploit the impossible physics" scenarios in as much as the possibility of bringing disaster upon yourself and others is comparatively low. (ie. In other scenarios it is comparatively simple/probable for the universe to just to throw a metaphorical meteor at you and kill everyone nearby as a way to stop your poorly calibrated munchkinism.)
It's actually surprisingly difficult to arrange situations where there's a chance of death but no chance of horrific incapacitation.
I shall assume you mean "sufficiently low chance of horrific incapacitation for your purposes".
It isn't especially difficult for the kind of person who can get time travelling prophets to give him advice to also have a collaborator with a gun.
I have to admit, you've sort of lost me here.
Call P1 the probability that someone who plays Russian Roulette in a submarine will survive and suffer a debilitating injury. P1 is, I agree, negligible.
Call P2 the probability that someone who plays Russian Roulette in a submarine and survives will suffer a debilitating injury. P2 is, it seems clear, significantly larger than P1.
What you seem to be saying is that if I know with certainty (somehow or other) that I will die in an airplane, then I can safely play Russian Roulette in a submarine, because there'...
Imagine looking at your hand, and knowing nothing of cells, nothing of biochemistry, nothing of DNA. You’ve learned some anatomy from dissection, so you know your hand contains muscles; but you don’t know why muscles move instead of lying there like clay. Your hand is just . . . stuff . . . and for some reason it moves under your direction. Is this not magic?
This was the theory of vitalism ; that the mysterious difference between living matter and non-living matter was explained by an Élan vital or vis vitalis. Élan vital infused living matter and caused it to move as consciously directed. Élan vital participated in chemical transformations which no mere non-living particles could undergo—Wöhler’s later synthesis of urea, a component of urine, was a major blow to the vitalistic theory because it showed that mere chemistry could duplicate a product of biology.
Calling “Élan vital” an explanation, even a fake explanation like phlogiston, is probably giving it too much credit. It functioned primarily as a curiosity-stopper. You said “Why?” and the answer was “Élan vital!”
When you say “Élan vital!” it feels like you know why your hand moves. You have a little causal diagram in your head that says:
But actually you know nothing you didn’t know before. You don’t know, say, whether your hand will generate heat or absorb heat, unless you have observed the fact already; if not, you won’t be able to predict it in advance. Your curiosity feels sated, but it hasn’t been fed. Since you can say “Why? Élan vital!” to any possible observation, it is equally good at explaining all outcomes, a disguised hypothesis of maximum entropy, et cetera.
But the greater lesson lies in the vitalists’ reverence for the Élan vital, their eagerness to pronounce it a mystery beyond all science. Meeting the great dragon Unknown, the vitalists did not draw their swords to do battle, but bowed their necks in submission. They took pride in their ignorance, made biology into a sacred mystery, and thereby became loath to relinquish their ignorance when evidence came knocking.
The Secret of Life was infinitely beyond the reach of science! Not just a little beyond, mind you, but infinitely beyond! Lord Kelvin sure did get a tremendous emotional kick out of not knowing something.
But ignorance exists in the map, not in the territory. If I am ignorant about a phenomenon, that is a fact about my own state of mind, not a fact about the phenomenon itself. A phenomenon can seem mysterious to some particular person. There are no phenomena which are mysterious of themselves. To worship a phenomenon because it seems so wonderfully mysterious is to worship your own ignorance.
Vitalism shared with phlogiston the error of encapsulating the mystery as a substance. Fire was mysterious, and the phlogiston theory encapsulated the mystery in a mysterious substance called “phlogiston.” Life was a sacred mystery, and vitalism encapsulated the sacred mystery in a mysterious substance called “Élan vital.” Neither answer helped concentrate the model’s probability density—helped make some outcomes easier to explain than others. The “explanation” just wrapped up the question as a small, hard, opaque black ball.
In a comedy written by Molière, a physician explains the power of a soporific by saying that it contains a “dormitive potency.” Same principle. It is a failure of human psychology that, faced with a mysterious phenomenon, we more readily postulate mysterious inherent substances than complex underlying processes.
But the deeper failure is supposing that an answer can be mysterious. If a phenomenon feels mysterious, that is a fact about our state of knowledge, not a fact about the phenomenon itself. The vitalists saw a mysterious gap in their knowledge, and postulated a mysterious stuff that plugged the gap. In doing so, they mixed up the map with the territory. All confusion and bewilderment exist in the mind, not in encapsulated substances.
This is the ultimate and fully general explanation for why, again and again in humanity’s history, people are shocked to discover that an incredibly mysterious question has a non-mysterious answer. Mystery is a property of questions, not answers.
Therefore I call theories such as vitalism mysterious answers to mysterious questions.
These are the signs of mysterious answers to mysterious questions:
1 Lord Kelvin, “On the Dissipation of Energy: Geology and General Physics,” in Popular Lectures and Addresses, vol. ii (London: Macmillan, 1894).
2 Lord Kelvin, “On the Mechanical action of Heat or Light: On the Power of Animated Creatures over Matter: On the Sources available to Man for the production of Mechanical Effect,” Proceedings of the Royal Society of Edinburgh 3, no. 1 (1852): 108–113.
3 Silvanus Phillips Thompson, The Life of Lord Kelvin (American Mathematical Society, 2005).