Question or statement?

This is a passage from a poem:

What is love, but the passion I feel in my heart?

What is passion, but the energy of my soul?

What is my soul, but a fountain of emotions erupting?

My question is, should those lines end with a question mark or period.


Solution 1:

It's dangerous to apply the grammar of prose to poetry. Here's, the punctuation changes the poet's observations on the nature of love. With periods, she has solved the mysteries of the heart. With question marks she at least acknowledges she might be just as lost as the rest of us.