Half as many people will not support half as many enterprises In a given geographical territory, half as many people will not support half as many such enterprises spaced at twice the distance. When distance inconvenience sets in, the small, the various and the personal wither away. Jane Jacobs, The Death and Life of Great American Cities densitydistancegeographybusinesseconomics
Economy of material and labor Whatever the comparative merits of [various bed framing methods], what is clear from Aristotle's Mechanica is that economy of material, and labor, was as much an issue in ancient times as it is now. Henry Petroski, The Evolution of Useful Things The requirements of economyThe art of not constructing simplicity