Interesting fact: the brain circuit we use to curse is not the one we use for normal speech. It is, however, the same circuit that monkeys use to warn others of predators. And you can kinda see how humans would use it the same way with anything perceived as a threat: “*bleep* this stupid computer!!” used to be “kill that sabertooth tiger!!” back when we lived in caves and tents. IMHO, certain words became taboo because they were only to be used in emergencies, and then humans just kept getting safer and safer so there were fewer emergencies.

There are still appropriate ways to use curse words. Even the Bible has several, though our English translations usually soften them. A few examples: Jesus called Herod a “fox” — actually a much more derogatory term, similar to the b-word. Paul says he counts his Jewish advantages as “rubbish” — actually a much stronger term, meaning manure (extrapolate to our current taboo toilet terms).

Personally, my husband and I agree that our kids can only use swear words once they learn how to use them right. Like sharp knives, matches, or power tools. Useful, but not to play with.