Madness alone is truly terrifying, inasmuch as you cannot placate it either by threats, persuasion, or bribes.
 Joseph Conrad, The Secret Agent (1907). copy citation

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Author Joseph Conrad
Source The Secret Agent
Topic madness persuasion
Date 1907
Language English
Reference
Note
Weblink http://www.gutenberg.org/files/974/974-h/974-h.htm

Context

“To that last they can always say: ‘Oh! it’s mere class hate.’ But what is one to say to an act of destructive ferocity so absurd as to be incomprehensible, inexplicable, almost unthinkable; in fact, mad? Madness alone is truly terrifying, inasmuch as you cannot placate it either by threats, persuasion, or bribes. Moreover, I am a civilised man. I would never dream of directing you to organise a mere butchery, even if I expected the best results from it. But I wouldn’t expect from a butchery the result I want.” source