I suspect concepts like fate, destiny, happenstance, kismet, etc. are meaningless and, worse, misleading to non-critical thinkers but I find myself using expressions involving luck or lucky all the time! 'Luckily another bus turned up so I wasn't late.' It seems to be the same thing as fate, etc. but seems unavoidable and even useful in everyday speech. Is there any difference, or is it just a linguistic convention? No one would say 'A causal chain of events extending back to the Big Bang led to another bus showing up.'
Thanks to you all for a fascinating site.
You should have a look at answers on this site under the heading of Probability, but briefly: Yes, 'lucky' is a useful and meaningful concept in everyday language. It means: something that I judge relatively unlikely happened that I judge useful to me. It differs from a concept like fate because we are talking about measurable and widely-understood probabilities, and not mysterious chains of events reaching back centuries. It is important that it happen to me, of course; the guy standing next to me at the bus stop may have felt very unlucky. He was hoping there wouldn't be a bus, and then he would have an excuse for not showing up at some boring philosophy lecture.