See
https://languagelog.ldc.upenn.edu/nll/?p=2290 for some details. I would summarize by saying, there were words involved (i.e. the Latin "petitio" and Greek "αἰτεῖσθαι") that have multiple meanings (a modern analogue being "plead", which can mean "ask"/"beg", but can also mean "plead to the court [some statement of fact]"—i.e. to make a claim), and the word "beg" comes from a translator selecting one of the wrong meanings. Also, "the question" is really a poor choice to mean "the original point to be proven"/"the conclusion"/"the point in question".
I am strongly against prescriptivism telling people that a bad translation that makes no sense is correct. I recommend "assuming the conclusion" as a correct name.