Edmond Halley (the astronomer and polymath who studied Halley's Comet) made a similar observation in 1693 after compiling the first modern mortality table.

> [I]t may perhaps not be an unacceptable thing to infer from the same Tables, how unjustly we repine at the shortness of our Lives, and think our selves wronged if we attain not Old Age; whereas it appears hereby, that the one half of those that are born are dead in Seventeen years time, 1238 being in that time reduced to 616. So that instead of murmuring at what we call an untimely Death, we ought [...] to account it as a Blessing that we have survived, perhaps by many Years, that Period of Life, whereat the one half of the whole Race of Mankind does not arrive.

1. http://www.pierre-marteau.com/editions/1693-mortality.html