Just as a counterpoint, in the book "Moonwalking with Einstein", the author talks quite a bit about the fact that many of these methods survived for a long long

Just as a counterpoint, in the book "Moonwalking with Einstein", the author talks quite a bit about the fact that many of these methods survived for a long long time, and people in the past considered memory an incredibly important proof of someone being educated. The methods seem to have been "lost" mostly when better options for external memory (e.g. writing and printing) became more universal. (iirc - i'm probably messing this up somewhat).