George Santayana - "Dreamt I to-day the dream of yesternight" lyrics

Dreamt I to-day the dream of yesternight, Sleep ever feigning one evolving theme,-- Of my two lives which should I call the dream? Which action vanity? which vision sight? Some greater waking must pronounce aright, If aught abideth of the things that seem, And with both currents swell the flooded stream Into an ocean infinite of light. Even such a dream I dream, and know full well My waking pa**eth like a midnight spell, But know not if my dreaming breaketh through Into the deeps of heaven and of hell. I know but this of all I would I knew: Truth is a dream, unless my dream is true.