How would you explain ‘all on a chance’ in the context?
It’s strange every time, returning to the Allende Street house where Señora Frida marched home from the Melchor market that birthday long ago, a stranger, with a shy boy carrying her bags because Every Man has the Right to make a Kite from his Pants. And in the courtyard inside, the Painter sat under the trees reading his newspaper, waiting to be found, all on a chance. How strange that a boy could make a kite of his pants, fly them around the world, and somehow arrive back at the house where everything began.
How would you explain ‘all on a chance’ in the sentence: the Painter sat under the trees reading his newspaper, waiting to be found, all on a chance?
Thanks!
PS: It's from The Lacuna by Barbara Kingsolver.