Sidney's Sonnet 31 is replete with clever and often humorous plays on words as wordplay is an important quality in a Renaissance courtier and writer. J.C.A. Rathmell contends that Sidney's poetry is
...characterized by the frequent appearance of a sly and sutle wit that is always threatening into question, albeit affectionately, the heroic and romantic values it ostensibly celebrates.
One example of this wit is the poet's addressing the moon as though it were lovesick like him when in this address to the "Moon" he calls upon the classical image of mythology, but Diana is the goddess of the moon and a perpetual virgin who is not moved by love. Sidney's good-humored scrutiny mocks his characteristic over-elaboration, as well.
In this Petrarchan sonnet, the eight-line octave raises a question and presents a problem. Then, the six-line sestet answers the question and solves the problem, or comments upon the narrative.
Thus, in the octave, the poet senses a sympathy with Nature, or pathetic fallacy. The Moon seems melancholy, just as the poet does. Is love, then, he asks, inconstant in the heavens as well as on earth? "Is constant love deemed there but want of wit?" i.e., is love that is faithful only for those who are not smart? Are beauties in the heavens as "proud" as they are on earth?
In the sestet, then, the poet asks if the beauties in heaven enjoy being the objects of love, but mock those who love them. And, while they wish to be loved, do they yet display scorn and ingratitude for those who do so? i.e. Are they as ungrateful as those on earth, only in love with being in love, not in love with the men?
In Sonnet 31, Sidney raises questions about the paradoxes of love. Is love desired, yet this desire derogated as a lack of intelligence? And, are the fair beauties so proud that they scorn love, yet at the same time they desire it?