Sonnet 73 employs nature as a conceit to convey the speaker's fading existence. Autumn imagery acutely illustrates the state of the speaker who was once imbibed with vitality like that of the trees in the full bloom of summer, but are now nearing their autumnal abscission, just as the speaker's death approaches. The trees have lost almost all their foliage, yet line two demonstrates the speaker's uncertainty of how soon autumn will fade into winter (his impending death) stating, "when yellow leaves, or none, or few, do hang." Just as the time of the speaker's death remains unclear, the indistinct imagery of the leaves reflect this uncertainty, as the speaker cannot sense how many, if any, leaves cling to the branches of the tree. The speaker is not the only one conscious of his impending death as he addresses someone who recognizes the speaker's fading life, yet nevertheless loves the speaker with an enduring love. The last line of the poem seems somewhat didactic by nature, as it suggests that one must love with all one has throughout life, as life will inevitably fade away just as every summer fades into autumn. The conceit of sonnet 73 bore a strikingly similar resemblance to the conceit of sonnet 97. Although seasons embody the passage of time in both poems, poem 73 refers almost exclusively to autumn. Sonnets 71, 72, and 74 all address the theme of death as well, yet they address death more directly rather than relying heavily upon metaphor.