Pedant’s Paradox: Kavka’s Toxin

Pedant’s Paradox

About the series: Examining logic problems and paradoxes and dismantling them, because I am just that picky. Feel free to debate my answers. (Yes I am aware most of these have mathematical answers, but they’re dressed¬† in real-world examples so they can be looked at with real world logic).

The Problem: A billionaire will give you £1 Million if the next day at noon you take a pill that will make you violently ill for 24 hours, after which you will recover fully with no side effects. However, to earn the money, you must form the intention of taking the pill at midnight the night before. After midnight you can back out of taking the pill with no penalty and still receive the money.

The Answer: Gregory Kavka who created the problem stated it was impossible to form the intention at midnight as everyone would undoubtedly back out rather than be sick the next day.

This is provably false just by the existence of drug testers, live organ donors etc.

It is possible to form and hold the intention to do something even if you know it will be unpleasant if the incentive is high enough. Many generation of people have gritted their teeth through family gatherings for less incentive than $1 million.

How many people have agreed to do something they don’t like, despite knowing they could back out with no consequences? Seeing that awkward relative is normally arranged in advance, but you can phone and plead illness or cancel at any point with no issues – and yet some people carry it through.

Kavka assumes it is impossible to form the intention because obviously you will back out rather than get sick. The problem is that for anyone whose word is their bond, once they have agreed to the billionaire’s deal to take the toxin it is binding and therefore if they agree the day before they will, at midnight that night, have a sincere intention of taking the toxin. Failing to do so gives them the alternative that they have broken their word, which is less desirable than being ill for 24 hours. A problem that fails if the individual is honourable is not a very good problem.


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