Cancer and Cost-Benefit Analyses
The problem with cancer is not so much the physical pain and detriment, but the way it disrupts our internal cost-benefit analysis. When it comes to life-or-death situations, the costs and benefits are seemingly unlimited. Death is an infinite loss, and prolonged life, even for six months, feels like an infinite benefit.
We have some capacity to make life-or-death decisions frequently, such as swerving out of the way to avoid a car accident. But the probability of success in those situations is close to 100%. In the case of cancer, if treatment has a 20% chance of prolonging your life another 10 years along with a 100% chance of six months of suffering, then our decision-making breaks down. Theoretically, we could discount the future by some amount, but Expected-Value Theory doesn't work when it comes to life-or-death and uncertain outcomes. The expected value of 20% multiplied by 10 years is 2, but you can't say, "this choice is worth two years." Utilitarians would reply that you can factor in your risk-aversion and you could add extra negative weights to pain. But then the cancer patient would also have to apply cost-benefit analyses to the decision-making process. It's incredibly stressful to come to the conclusion to not do therapy when its odds of success are 20% or greater. Those odds are enough to activate hope within us, and as much as we can discount the future value of extra days of life, we're wired to feel still like it has infinite value.
Towards the end of our lives, we desperately grasp at treatment after treatment, even as their efficacy runs out. This kind of grasping was useful for our survival in the past, such as the perseverance in the face of famine. But the nature of cancer has driven us to make last-ditch efforts a way-of-life. Doctors will urge us not to throw good money after bad when it comes to fighting cancer, but we, as patients, demand otherwise.
The standard way to model the time factor in cost-benefit analyses is to discount the future. For most people, gains in the present are worth more than gains in the future. But time doesn't have to matter to us. Some adults, when they have children, for example, begin to exist in a timeless universe, one where they live just to monitor the growth of their children. Their main costs and benefits have been subsumed into their spawn. Should we go on vacation or not? It doesn't matter, because their children are living out their lives. Whether a decade or two passes by for the parents, it's no bother, since it's the arc of their children's story, something they can't control, that matters.
So the rationalist would find another function, a global discounting of costs and benefits. But, as the layers of discounting functions increases, so does the risk of overfitting, thus rendering analysis meaningless. Sometimes, there are zero costs, zero benefits, over zero time, leading to division by zero somewhere, making the whole calculus undefined.
Rationality is a ritual, one that involves light, vague estimates of costs and benefits
They're so light, that one wonders if they can even be called rational. For example, when you ask for help and someone volunteers it, neither party is really measuring cost-benefit because the stakes are so low. Rather, all our actions are just a matter of drives and culture. Likewise, in the case of voting, it's not a rational decision for most of the electorate.
The Usefulness of Accuracy
Accurate statements aren't necessary, or even useful. For example, if your child gets mugged while walking down an alley in a rough neighborhood, then according to law and accuracy, the cause of their mugging was the mugger. Many other people have walked down that alley in that neighborhood and not gotten mugged. But you would still scold your child until they promise not to walk down that alley again, because that's what's most likely to prevent them from getting mugged in the future. You can cause your child to be less mugged in the future by blaming them for their mugging in the past.