My foothold is tenon’d and mortis’d in granite,
I laugh at what you call dissolution,
And I know the amplitude of time.

These lines come from Walt Whitman’s long poem “Song of Myself,” first published in the inaugural 1855 edition of *Leaves of Grass* and repeatedly revised across Whitman’s lifetime. In the poem, Whitman adopts a prophetic, expansive speaking voice that fuses body and soul, individual and cosmos, and treats death not as an ending but as a transformation within nature’s cycles. The diction of carpentry (“tenon’d and mortis’d”) reflects Whitman’s fondness for concrete American work-terms, while the defiant tone belongs to the poem’s broader project: asserting a self and a democratic spirit that cannot be reduced by conventional pieties about mortality or decay.

The speaker claims an unshakable grounding—his “foothold” is joined into “granite” as firmly as a mortise-and-tenon joint—suggesting a self rooted in the material world and in enduring natural law. “Dissolution” (the breaking down of the body, the fear of death, or the disintegration of identity) is mocked as a merely conventional label: what others call ending is, for Whitman, part of a larger continuity. The final line widens the scale from personal survival to cosmic duration; to “know the amplitude of time” is to perceive existence as vast, ongoing, and inclusive, where change and decay are absorbed into a larger, affirmative vision of being.