But mathematics is a subject which depends on understanding, not memory, "says Shih. Therefore he conducts a thought experiment with the class, to help them understand how this" illusion "comes about.
「一般老師都說是錯覺，以前思考往往就停在這裡，但數學是講道理的課，不是記憶的課。」所以我們要進行實驗，瞭解這個「覺」是怎麼「錯」的？