Read this excerpt from "On Virtue," by Phyllis Wheatley. O thou bright jewel in my aim I strive To comprehend thee. Thine own words declare Wisdom is higher than a fool can reach. I cease to wonder, and no more attempt Thine height t’explore, or fathom thy profound. But, O my soul, sink not into despair, Virtue is near thee, and with gentle hand Would now embrace thee, hovers o’er thine head. Fain would the heaven-born soul with her converse, Then seek, then court her for her promised bliss. What is the main difference between Wheatley’s “On Virtue” and Frost’s "Mending Wall"?