At work, you can buy reasonable time: "let me get back to you"
Outside work, people remember/invite people who are empathetic and/or fun to be around, not those who win arguments. In fact argument winners tend to annoy people more.
There are very few high-stakes situations where quick thinking is crucial. What most people mistake for quick thinking (say averting a mishap during airplane landing) is trained muscle memory, which comes from long prep.