Flip, remember, match.
Turn over two face-down cards. Match them and you keep the pair and go again; miss and they flip back for your opponent. Most pairs wins. Pure memory.
A matching game that spread worldwide through playing cards, known in English as Concentration. Its blunt Japanese name, shinkei-suijaku, comes from a medical term imported in the Meiji era that stuck to the game.
Open with a card you do not know. Turn an unknown card first and a known card second: even a miss hands you new information. And watch every card your opponent flips.
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