"Every perception is to some degree an act of creation, and every act of memory is to some degree an act of imagination."
-- Gerald Edelman, Second Nature: Brain Science and Human Knowledge
2 Two cheers for mnemonic techniques4 Two cheers for mnemonic techniquesTwo cheers for mnemonic techniquesHow can we develop transformative tools for thought？2020-10-18Journal
Given all this, it's perhaps not surprising that we often meet people who tell us that mnemonic techniques are a much more promising approach to memory than ideas such as spaced repetition.
We're enthusiastic about such mnemonic techniques. But it's important to understand their limitations, and not be bedazzled by the impressiveness of someone who can rapidly memorize a deck of cards.
One caution concerns the range of what can be memorized using mnemonic techniques. In practice they're often quite specialized. Mnemonic experts will, for instance, use somewhat different approaches to memorize lists of digits versus decks of cards. Those approaches must be mastered separately – a heavy time investment for two narrow kinds of memory. Furthermore, the mnemonic techniques tend to be much better suited for concrete objects than abstract conceptual knowledge – it's difficult to store, say, the main points in the Treaty of Versailles in your memory palace. This doesn't mean it can't be done – mnemonic experts have developed clever techniques for converting abstract conceptual knowledge into concrete objects which can be stored in a memory palace. But, in general, an advantage of spaced repetition is that it works across a far broader range of knowledge than do any of the mnemonic techniques.