[DennisP]

One proposal is the Novikov self-consistency principle.

Imagine a billiard table with a wormhole, which curves and goes three seconds backwards in time. It's set up so you can roll a ball into the wormhole, and it will emerge three seconds earlier and knock itself off the path, so it doesn't enter the wormhole. Paradox!

Except actually it emerges with a slightly altered path, and strikes itself only a glancing blow.

And why did it emerge with an altered path? Because it was struck a glancing blow.

https://en.wikipedia.org/wiki/Novikov_self-consistency_princ...

[sullyj3]

So, circular causality, basically?