Definition, or the speaker’s attempt to define an object (in this case, the concept of “heart”), is the core theme in “Heart to Heart,” driving the argument and lyrical arc. “Heart” is a complicated idea, and Dove’s goal in writing this poem is to explore its various definitions as they relate to the speaker. Line 1 begins, “It’s neither red / nor sweet” (Lines 1-2), immediately discrediting two common metaphorical turns of phrase. This line of thought continues, “It doesn’t melt / or turn over, / break or harden” (Lines 3-5). Following this list of what the heart is not, the speaker then deduces that if the heart is not these things, “it can’t feel / pain, / yearning, / regret” (Lines 6-9). Through the act of trying to define the heart, the speaker comments on the difference between the literal and metaphorical heart.

Line 10 begins again with another attempt at definition: “It doesn’t have / a tip to spin on, / it isn’t even / shapely” (Lines 10-13). Again, the speaker uses negation, followed by affirmative lines: “just a thick clutch / of muscle, / lopsided, / mute” (Lines 14-17). This repeated action—of using negation to define what the heart is not, followed by a description of what the heart is—creates a consistency in the poem, an expected pattern.