Final answer:
The central idea of the excerpt from Chapter 3 of Why We Love is the diverse exploration of love by sixteenth-century poets as part of the human experience, highlighting the joy in examining this essential emotion.
Step-by-step explanation:
The central idea or theme in the excerpt from Chapter 3 of Why We Love deals with the exploration of human existence through the emotion of love by different poets in the sixteenth century. Despite the varying approaches of these poets, the underlying theme is consistent with the joy and complexity in examining love as an integral part of the human condition. The excerpt touches on critical thinking about big questions such as the beginning of time and space and the values and principles at the foundation of societies, encouraging readers to form various perspectives on these grand concepts.