Robert Hass is a living poet who represents the contemporary American poetry. Hass`s poetry reveals basically a monistic epistemology. The belief that there is "a first world" of unity beyond the divided changing world of appearance is the basis of his monistic epistemology. This poetic attitude is evoked by the nostalgic wish to recover "a first world/of undivided light" and he sometimes glimpses eternity in the world of appearance on the journey towards the recovered first world. F. H. Bradley was a leading philosopher who revolted against dualism by proclaiming a monistic epistemology where subject and object form a unity as a living whole. Hass`s poetry shows an affinity with Bradley`s epistemology which consists of the three following stages of awareness: "immediate experience," "the relational consciousness" and "the supra-relational" consciousness. This paper examines the relationships between reality and appearance, and the three stages of awareness revealed in some of Hass`s major poems including "Meditation at Lagunitas," "Natural Theology" and "Mouth Slightly Open" in the light of Bradley`s epistemology, which eventually helps to elucidate the nature of Hass`s poetry.