Matteo Ricci is also known for being one of the pioneers of mnemonics. Some of the techniques he employed were known in the middle ages before printed books (in

Matteo Ricci is also known for being one of the pioneers of mnemonics. Some of the techniques he employed were known in the middle ages before printed books (in the West), but he wrote one of the first treatises on mnemonics. A Jesuit once told this was because he wasn't allowed to bring books into China and so he had to memorize everything, but I can't find confirmation of this claim.