The arts intellectual are four in number, divided according to the ends whereunto they are referred—for man’s labour is to invent that which is sought or propounded; or to judge that which is invented; or to retain that which is judged; or to deliver over that which is retained. So as the arts must be four—art of inquiry or invention; art of examination or judgment; art of custody or memory; and art of elocution or tradition.
— Francis Bacon in “The Advancement of Learning”, Second Book Chapter XII
This four-part division is based on the ends and aims of human endeavour. Man finds what he has been looking for, judges what he has found, retains what he has judged and transmits what he has retained.
— From Paoli Rossi, “Logic and the Art of Memory”
Further Reading:
https://www.gutenberg.org/files/5500/5500-h/5500-h.htm
https://plato.stanford.edu/entries/francis-bacon/#Ido
Paoli Rossi / Logic and the Art of Memory: the quest for a universal language
The Four Idols of Francis Bacon
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Makes sense. Thanks for bringing memories of Sir Francis back to my conscious brain. I remember trying to fathom him when my mom got the Great Books when I was a young boy.