One of the lessons I learnt maybe even as a primary school kid is that my father hated folks who "beat his abacus". He used to say in Cantonese that you should never let someone 打你的算盘.
I was doing some research just now and it seems to be related to the idiom "to beat a small abacus" or 打小算盘 which has a totally different meaning which is to be very petty-minded about money.
To understand the context of my family
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