A quote attributed to
John Maynard Keynes, as a
catch phrase in his
rebuttal to
laissez faire economics, as proposed by
Adam Smith. The idea is that rather than
"in the long run, everything will even out", that
"in the long run, we're all dead", so we should aggressively push to rectify
economic problems (
within our lifetimes), rather than just
letting everything work itself out.
If you're not into economics, and have fatalistic tendencies, you might just want to use this phrase wherever it fits; it tends to rile people up, which is always an enjoyable activity...