This section is dedicated to the influence the stars and constellations have on the world 1.
As Ramchal already explained 2, everything material is ultimately rooted one way or another in the Transcendent Forces 3. But then that phenomenon needs to somehow be transported downward 4 and be “brought down to earth”, so to speak, and to assume one thing or another 5.
That’s the function that the stars and constellations serve 6. It’s thanks to them and everything associated with them 7 that the spiritual phenomena are transported downward from their spiritual state to our material world in a form 8.
Now, the number of stars, their relative status, and their differences was devised by the highest wisdom so as to best and most elegantly bring about this transport downward.
The ability of physical things to go on 9 is thanks to the influence of the stars, given explicitly that they transfer phenomena from their sources in the highest heavens to their earthly role.
Footnotes:
1 It’s ironic that we in modernity are more thunderstruck by the lights on the ground when our plane descends at night over a city than by the sight of millions of stars in the sky. The ancients, though, were nonplussed by the galaxies over them. They realized their power while we simply don’t. Hence, the modern aversion to the influence of the stars.
The truth of the matter is that not every traditional thinker accepted the influence of the stars. See Rambam’s remarks about that in his comments to Mishna Avodah Zara (which is puzzling knowing that he attributed soul, intelligence, and understanding to them – see Yesodei HaTorah 3:3; and see where he remarks that they are “means of governing His created beings” {Guide 2:5:3}!
See Sefer Haikarim 4:4 for arguments for and against.
2 See 1:5:2.
3 Which are themselves rooted in G-d’s will.
4 See 1:5:3 and 2:1:2 above.
5 Those Forces are exceedingly sublime, so a number of steps must be taken to reach down here.
6 See 1:5:1 above.
7 Like angels, for example.
8 See Shabbat 156a, Da’at Tevunot 174, Ramban to Deuteronomy 18:10, and Zohar Chadash 92c.
9 See Ma’amar Haikkurim, “Beruchaniyim”.