N: There are many texts in the Patisambhidhamagga and also in Commentaries.
He knows everything that he puts his attention to. Not everything at the
same time, since each citta only experiences one object at a time.
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The difficulty, for me, is this: unqualified omniscience implies that
everything is pre-determined. If a Buddha knows everything to which he puts
his attention, then he must know all future events. To be able to know
them, they must necessarily be already fixed or pre-determined. So, if I
roll a pair of dice, a Buddha would know, if he puts his attention to it,
the outcome. The outcome is no longer the result of chance as gamblers
might assume. In the case of individual actions, this also means that there
is no free-will -- one's choice of actions are fixed and pre-determined
since it is or can be known in advance by a Buddha. This seems to be a big
problem which will lead to the same kind of sophistry to which theistic
religions must resort in order to explain the reality of free-will even
though God knows everything in advance.