People frequently discuss exponential population growth, but rarely mention the terrestial confines of such thinking.

Then they say, oh but technology will continue to advance, and yet never mention pioneering space travel.

I feel like economists that extrapolate numbers into the future, but fail to consider space travel are like holy men, refusing to consider that the earth is round, and rather than the imaginary center of a flat universe; doomsayers, warning that we'll sail over the edge, if we venture too far out to sea.