Can you help me understand this speech from Shakespeare's Temepst?

"Be cheerful, sir. / Our revels now are ended. These our actors,/ As I foretold you, were all spirits, and/Are melted into air, into thin air./ And, like the baseless fabric of this vision,/ The cloud-capp'd towers, the gorgeous palaces,/ The solemn temples, the great globe itself, /Yea, all which it shall inherit, shall dissolve." (Act 4 Scene 1, Lines 147).

This is one of Shakespeare's most beautiful speeches and its laden with hidden gems. Before analysis, you may feel better to get to grips with what it actually means on a surface level. In this scene, Prospero interrupts the marriage celebrations ("the revels now are ended") of his daughter Miranda to make this speech to her new husband Ferdinand (the "sir" of the first line.) He tells him all the aspects of the previous celebrations were acted by spirits and are not real, thus, they 'melt into air' as if they never existed. He also then goes off on a bit of a tangent, and meditates not only about the 'fakeness' of the celebrations he created himself, but the artificiality of life in general. "This vision" refers (in a sneaky bit of metatheatre that is extended in the speech) to the life he leads on stage in the artificially created world of the play, made up of "towers", "palaces", "temples" etc. He even refers to the Globe itself, where most of Shakespeare's plays were performed. This, like all other apsects of human life (the fictional lives enacted in the play or those of reality) won't last forever, and will also eventually fade. The next three lines (which I haven't included here) are pretty famous and point to some important themes that are at work in the play-which we can unfold together once we're confident about the rest of the speech.