Men are not made to be crowded together in ant-hills, but scattered over the earth to till it. The more they are massed together, the more corrupt they become. Disease and vice are the sure results of over-crowded cities. Of all creatures man is least fitted to live in herds. Huddled together like sheep, men would very soon die. Man's breath is fatal to his fellows.
 Jean-Jacques Rousseau, Emile, or On Education (1762). copy citation

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Author Jean-Jacques Rousseau
Source Emile, or On Education
Topic vice crowd
Date 1762
Language English
Reference
Note Translated by Barbara Foxley
Weblink http://www.gutenberg.org/cache/epub/5427/pg5427-images.html

Context

“But if this friend cannot be found, if this transfer is not easy, if none of my advice can be followed, you will say to me, "What shall I do instead?" I have told you already—"Do what you are doing;" no advice is needed there. Men are not made to be crowded together in ant-hills, but scattered over the earth to till it. The more they are massed together, the more corrupt they become. Disease and vice are the sure results of over-crowded cities. Of all creatures man is least fitted to live in herds. Huddled together like sheep, men would very soon die. Man's breath is fatal to his fellows. This is literally as well as figuratively true. Men are devoured by our towns. In a few generations the race dies out or becomes degenerate; it needs renewal, and it is always renewed from the country.” source