Well this is not totally asinine tripping balls insane, I mean we could develop biofuel cells that implant in the body produce electricity by parasitically sucking off oxygen, sugar and ketones. Don't think we could make much power from them, maybe enough to power a pacemaker at first, maybe cybernetic implants like artificial eyes, ears, brain enhancers, etc, the cell would get really big if it had to power a prosthetic leg or arm or produce meaningful power outside the body. Batteries would certainly provide greater power density by order of magnitude even if they could not operate off you as long as your alive like a biofuel cell could. I was presented evidence that studies have been done that claim that happiness is lower for parents then for singles, if you want a primary source, go find one, the argument was not in the validity of such evidence but in its subjectivity, parents could claim their suffering does not exist, that such studies did not measure the factors of happiness that children cause, that having children causes massive gratification because you followed instinct and push your genes on another generation like a good animal, etc, etc. Now I don't care what you implied at first you have brought up to me a interesting paradox: Nazis did in fact create science to back up their cause, be it fabricated or not, for example Nazis found that smoking was unhealthy and damaging to the social health of their "aryan race", since Nazis discovered this it must be wrong and we should smoke as a little "fuck you" to fascism or refusing to smoke for cited health reasons is appeasement to fascism! So your fine with the fireman scenerio, now lets raise the stakes on ethics and guilt: the police man scenario! Your a police officer and your in a stand off between a craze gun man on the right and two civilians on the left that he shooting at, who do you shoot and kill? easy right, now lets say its 1 gun man on the left and 2 gun men on the right shooting at each other, let them kill each other? Kill the one on the left so the others stop shooting? Now lets put all this together in a ethical cluster fuck: lets say a timetraveler from the future, appears before all humanity, incontrovertible scientific proof that we need to kill off aaah say all the Muslims, yeah, because in a few decades they will unless nuclear jihad and destroy humanity, should we undertake mass genocide and kill hundred of millions of people systematically to save billions later? This is not like the Nazis, we arn't embarking on mass genocide simply because we dislike them, we are doing because of absolute proof that they will nuke the rest of us dead soon.