A2. There are recorded methods of exercises towards recalling the past: like all other exercises, only very rigorous practice would bring results. Theoretically, one starts by recalling what exactly happened, very precisely, the minute before, the day before, three days before, a week, a month, etc., until the proficiency is so great that one can recall what happened on a certain date instantaneously, then go further and further back. This exercise is useless in the accumulation of wisdom which is the main goal of the Buddha and not  central to the Buddha's teaching.

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