Welcome to the Grammar Minute, where we’re saving the English language sixty seconds at a time! I’m Lauren Smyth, and I’ve got a question for you: What does it mean to beg the question?
A lot of people say it means to raise a new question. If I say I’m never drinking coffee again, that begs the question: What is wrong with me? 
But this is the wrong way to use the phrase. “To beg the question” is to commit the logical fallacy of circular reasoning. If I say: “I’m never drinking coffee again, because I’ve decided to stop drinking coffee,” you would say: “Well, that begs the question.” Full stop. Nothing else is needed in that sentence.
“To beg the question” is a common idiom in today’s language, but it’s still wrong to use it as a synonym for “raises a question.” And once you hear it, you can’t un-hear it. As usual, it’s best to be strictly, technically correct in formal or written communication—even if people frequently use the phrase incorrectly.
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