Final answer:
The theme of Chapter 16 is the exploration of human existence through the examination of the emotion of love.
Step-by-step explanation:
The theme of Chapter 16 in the book 'Summer of the Mariposas' can be interpreted as the exploration of human existence through the examination of the essential human emotion of love. The three poets from the sixteenth century mentioned in the question are all exploring this theme, but in different ways. Each poet brings their own unique perspective and style to the exploration of love.