Typically when making the most important decision in one's life evidence would be reviewed, studied, discussed & evaluated.
I quite agree, assuming an individual intellectually strong enough to seek and evaluate the evidence absent the emotional baggage of acculturation and one's own desires.
In this case, unfortunately, there is no evidence to evaluate, dispassionately or otherwise.
Absent any evidence we have only speculations.
Speculations come in two kinds:
Formal Speculations and Absurd Speculations.
Formal speculations are those that are built upon a foundation of empirical first principles and have a strong (formal) logical path from first principles to the speculation. An example is the speculation of extra-terrestrial life. There is no empirical evidence of such but the logical path from empirical first principles (physics, chemistry, biology, cosmology) is very strong and lends credence to the efficacy of the speculation.
Absurd speculations have no such foundation in first principles. My favorite example, in keeping with a cosmological genre, is the existence out there of a planet wholly accreted from Philadelphia Brand Cream Cheese. Not any of that store brand generic stuff either but the real Kraft Philadelphia brand ... with chives. Again, like above, there is no evidence of such but there is also no logic from empirical first principles to support the speculation.
We treat these two speculations differently.
Formal speculations may, in appropriate instances, be treated as fact. In our example we see this when we reason why we should not only sterilize our space probes going out, but, sterilize the everlovin’ hell out of those parts we bring back.
Absurd speculations, on the other hand, must be ignored (in any valid scientific treatment) until evidence of efficacy can be shown.
For your purposes in this thread, there being no empirical evidence of what invisible metaphysical magician(s) may or may not exist (let alone which one(s) may be greater or greatest) leaves the matter of their existence as speculation. Couple this with the fact that there is no logical path that can connect any empirical first principles to anything metaphysical (by definition) means the speculations of invisible metaphysical magicians are absurd speculations and must be ignored.
Your quest for a method (an empirically-based process) to determine which god(s) is(are) greatest is doomed to failure.
Edited by AZPaul3, : The usual suspects like spelling and punctuation and syntax.
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