Our grandfathers were less well-housed, well-fed, well-clothed than we are. The strivings by which they bettered their lot are also those which deprived us of [Passenger] pigeons. Perhaps we now grieve because we are not sure, in our hearts, that we have gained by the exchange. The gadgets of industry bring us more comforts than the pigeons did, but do they add as much to the glory of the spring?
"A Sand County Almanac: And Sketches Here and There". Book by Aldo Leopold. Chapter "Wisconsin: On a Monument to the Pigeon", p. 109, 1949.