One who by himself is mild enough and void of all offence will become terrible and fierce by being in bad company, and will most cruelly take the life of many men, and would kill many more if they were not hindered by bodies having no soul, that have come out of caverns—that is, breastplates of iron.
 Leonardo da Vinci, The Notebooks of Leonardo Da Vinci (1478 – 1519). copy citation

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Author Leonardo da Vinci
Source The Notebooks of Leonardo Da Vinci
Topic offence life
Date 1478 – 1519
Language English
Reference
Note Translated by Jean Paul Richter in 1888
Weblink http://www.gutenberg.org/cache/epub/5000/pg5000-images.html

Context

“[Of Night when no Colour can be discerned.] * There will come a time when no difference can be discerned between colours, on the contrary, everything will be black alike. * [Of Swords and Spears which by themselves never hurt any one.] * One who by himself is mild enough and void of all offence will become terrible and fierce by being in bad company, and will most cruelly take the life of many men, and would kill many more if they were not hindered by bodies having no soul, that have come out of caverns—that is, breastplates of iron. * [Of Snares and Traps.] * Many dead things will move furiously, and will take and bind the living, and will ensnare them for the enemies who seek their death and destruction. * ( Of Metals. ) * That shall be brought forth out of dark and obscure caves, which will put the whole human race in great anxiety, peril and death.” source