Ellis: "Would it not be difficult to assume that good will overpower evil without that annoying thing that I find very important-- defining terms?"

I'll put these ideas to you for consideration:

What we humans recognise as good and evil are cosmic principles that are manifested through such sentient beings as are capable of the concept.

In a cosmos devoid of sentient beings, there would be nothing capable of holding those concepts. In that case the principles would remain unrealised.

Where there is a sentient being capable of such a concept, the concept is related to events that are either conducive or detrimental to the quality of its own existence and continued existence.

Such a being may be capable of inferring that what they recognise as good or evil is equally so to a similar sentient being - demonstrated by "doing unto others as you would have them do unto you".
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"Time is what prevents everything from happening at once" - John Wheeler