Which theme is prominent in this excerpt from "To an Athlete Dying Young" by A. E. Housman? Now you will not swell the rout Of lads that wore their honours out, Runners whom renown outran And the name died before the man. So set, before its echoes fade, The fleet foot on the sill of shade, And hold to the low lintel up The still-defended challenge-cup And round that early-laurelled head Will flock to gaze the strengthless dead, And find unwithered on its curls The garland briefer than a girl's. the inevitability of death