Jacob Riis, The Battle With the Slum (1902)

The wise men had their day, and they decided to let bad enough alone; that it was unsafe to interfere with "causes that operate sociologically," as one survivor of these unfittest put it to me. It was a piece of scientific humbug that cost the age which listened to it dear. "Causes that operate sociologically" are the opportunity of the political and every other kind of scamp who trades upon the depravity and helplessness of the slum, and the refuge of the pessimist who is useless in the fight against them.