Indeed. Abiogenesis comes to mind. The fundamental nature of time, too. As well as how measurement of quantum activity collapses the wave function. And how many licks it takes to get to the center of Tootsie Pop. The world may never know.

@resserts Abiogenesis maybe the most important question of all.

@Grecio I don't know… the Tootsie Pop question has been weighing on my mind for decades. (Seriously, I agree with you. Abiogenesis is a big hole in our knowledge, and it would be great if we had an answer or even a few good models to work with. So far, it's all speculation.)

@resserts The tootsie pop question might be similar to a quantum physics statistical experiment.
I once read of a computer program that is trying to calculate the statistical probability that the right chemicals could combine by accident into a replicator. Abiogenesis is, of course, all about replication.