By reading Golden Age comic books, Pre-COIE Earth-One Barry Allen learned that Jay Garrick was the Flash of Earth-Two. This wasn't a problem because there was no Jay Garrick (that we know of) on Earth-One, or even if there was, Earth-One's Jay Garrick wasn't the Flash.

But what about Superman (Clark Kent), Wonder Woman (Diana Prince), Batman (Bruce Wayne), Robin (Dick Grayson), and, to a lesser extent, Aquaman (Arthur Curry), Green Arrow (Oliver Queen), and Hawkman (Carter Hall)? These were heroes who existed on both Earth-One and Earth-Two, whom Barry knew as people in his world as well as characters in the comics he read. Were characters such as Superman, Wonder Woman, Batman, etc., simply different people (not Clark, Diana, Bruce, etc.) in the comics that Barry read? Or did their civilian identities never get portrayed in those comics? How did DC resolve this (assuming it ever did)?

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