We’re going to be drawing upon Ramchal’s Iggerot Pitchei Chochma V’Da’at 3 most especially to explain this section.
As he lays it out there, in point of fact “there are an infinite number of worlds” in the trace environment that is our reality — not just the few esoteric ones we’ll be focusing on. And Ramchal says as much in his comments to Petach 31.
What he does offer at the latter site besides that at this point, though, is this arresting definition of a “world”, which we’ll consider here before we go on with the rest of this section.
Ramchal understands a “world” as a system consisting of “a benefactor (משפיע) and a recipient (מקבל)”. That’s to say that each facet of reality — each “world” — must consist of an environment in which two polar opposite entities can form a mutually beneficial relationship and produce vital results , much like an electric circuit which, despite or most especially because of its polar opposite elements, manages to generate power.
Nonetheless, the point remains that there are an infinite number of worlds in the trace environment, even though we’ll be focusing in on just a few by necessity.
 We’re comparing the “benefactor” and “recipient” functions here to the reciprocally beneficial relationship of the “upper waters” of the heavens which are taken to be male and beneficent, and the “lower waters” of the earth which are taken to be female and receptive (see Breishit Rabbah 13:13; Zohar 1, 29b, etc.)
(c) 2011 Rabbi Yaakov Feldman
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