Great!
I'm in the middle of a war and a town is surrounded by enemies. To get better defense I have a great general in that city, but suddenly a great engineer appears and I'm told to do something about stacked units.
I could finish the wonder I'm building, but I have already built around 80% of it. But apart from that I cannot see any way to not have one of the great persons killed. Is there any solution to this?
And what would have happened if it was impossible to perform any action whatsoever with either of these great persons?