Three motifs in "The Triple Fool" are wise/wiseman, love/pain/grief, and fool. The motif of the fool may be the best for illustrating how motifs present and connect to a work's central ideas. Donne employs the fool motif four ways. Firstly, it is the substance of the title: this fool is a fool in three distinct ways. Secondly, the fool motif presents a central paradoxical idea which is that of the fool in love. Thirdly, Donne combines this motif with the wiseman motif and says that any wiseman who is not in love would gladly trade places with the fool if only the lady in question would stop rejecting the fool's love:
But where's that wiseman that would not be I,
If she would not deny?
Fourthly, the fool is a fool when he loves, when he expresses his love in poetry, and when others increase his grief and pain by turning his poetry into song.
And, by delighting many, frees again
Grief, which verse did restrain.
In the much simpler poem, "Ode to Enchanted Light," there are two dominant motifs, light and sky/air/world. The connection between the central ideas of the poem and light are fairly obvious, so the other motif may be best for illustrating the principles of presentation and connection in this poem. Combing both motifs, it is light that drifts from the sky, through the air, and fills the world. The central idea illuminated (presented/connected) by this sky/air/world motif is that light gives the world cleanness and goodness and life: "clean white sand"; "song / high into the empty air"; "overflowing with water."
Neruda's use of the light motif is probably metaphorical as well as literal since the last verse is a metaphor, though Neruda doesn't really give us enough substance in the poem for a definitive determination on this point:
The world is
a glass overflowing