aeternitas omnis = tuda a eternidade (all eternity)
totius mundi magnitudo = a grandeza do mundo inteiro (magnitude/grandeur of the whole universe)
What can seem great in human affairs to him who knows all eternity and the grandeur (magnitude, grandess, nobility) of the entire world? (lit. "to him for whom all eternity, and the magnitude of the whole universe, is known" )
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