According to DJ :
So, if I said to someone, "Go f**k yourself...", and they did and got
pregnant because of it, would that imply paternity and/or financial
responsibility?

"Reasonable person test" would fail ;-)

That said, a common "sample case" shown in law courses is where
a guy said to the wife of a friend "your husband just got killed
in a car accident" as a joke. Wife faints, falls down the stairs
and injures herself.

"Reasonable man test" says "a reasonable person would
know, or ought to have known that there was a good chance
it'd be believed, and if believed, something "bad" has a
reasonable chance of happening".

_That_ is civil assault.
--
Chris Lewis, Una confibula non set est
It's not just anyone who gets a Starship Cruiser class named after them.