The egg test: a model for reversible and irreversible decision making

Some talk of one way and two way doors, but I prefer the ’egg test’.

Do you want to know if it’s an egg?

… Drop it, if it cracks and you see an egg, then it’s an egg.

The egg test is irreversible

Clearly the problem here is that it’s now not possible to use that egg. This is an irreversible decision. That egg is never going to be hole again. And it’s going to be super hard to separate the egg, the shell, and whatever else was on the surface you dropped the egg on.

The problem with the ’egg test’ is not just that the decision is irreversible, but also that in trying to determine (observe) if an egg is an egg you change the state of the egg. “Schrodinger’s egg”, you might say.

How else to check an egg?

A quick google and apparently there are other, less destructive, methods for checking an egg. Something about if it floats or sinks. But this is still a proxy measure. There are other items that will exhibit the same floating or sinking behaviour as the egg. So you can approximate the result without destroying the egg, but you can’t be sure. You have to accept a small amount of risk / doubt. This is a reversible decision. I can take the egg out of the water and it’s pretty much back to how it was before I put it in the water.

Tradeoff: approximate vs. destructive

The ’egg test’ is a good example of using an approximate measurement to avoid destroying the egg. But really, you’re not going to find out if the egg is an egg without dropping it.