My student is referring here to Cunégonde, the lovely aristocratic inamorata of the eponymous character in Voltaire’s extraordinary satire Candide. They carom around the globe like balls on a warped billiards table, meeting, glancing off each other, spinning away, colliding…. Their adventures are bizarre and darkly hilarious; and, yes, through it all, Candide longs for Cunégonde and Cunégonde knows she loves Candide.
In Candide’s eyes—”eyes” in the sense of “view,” or “belief,” or “opinion”—Cunégonde is his destiny. In Cunégonde’s eyes—again, “eyes” in the sense of “view” etc.—Candide is her destiny.
So what’s so wrong with my student’s sentence?
First of all we have an unfortunately placed adverbial prepositional phrase. Moved to the beginning of the sentence, “in both their eyes” would more clearly modify the sentence as a whole via its verb “were destined”: in their opinions, they were destined to be together. At the end of the sentence, though, the phrase can seem to be answering “where?” about “be together,” just as “in Peoria” would work in the sentence “She and Harold were destined to be together in Peoria.” They are destined to be together in their eyes. If such a thing is possible. Eeuuw.
And then we have that unlikely but very real student-writing Waterloo, “both.” Students stick it in all sorts of places in all sorts of sentences, trying to signify a unanimity of purpose, feeling, experience, or what-have-you. Most often they wind up suggesting collaboration or conjunction where there is none and never was any. I could give examples here, but the examples I have are interesting in their own right and deserve separate treatment. Something to look forward to!
Meanwhile, the fact that most eyes come in sets of two adds further confusion to the phrase “in both their eyes.” Do they have only two together, as the Fates shared but one when they wanted to see the future? In Candide, two one-eyed lovers would be no more surprising than the Old Woman With One Buttock. Voltaire may have missed a really good idea there….