Some people are so much sunshine to the square inch.

The line is a compact metaphor for a person whose presence feels warming, enlivening, and disproportionately radiant—“sunshine” measured not in total quantity but in density (“to the square inch”). It suggests charisma or benevolence that seems to emanate from every small gesture, implying an almost physical intensity of cheer or vitality. The phrasing also carries a faintly humorous, colloquial precision (as if one could calculate brightness), which makes the compliment vivid and memorable. Even when detached from a verified Whitman context, the sentiment aligns with a broader nineteenth-century tendency to describe temperament in terms of light, warmth, and natural force.