In psychology, ontological, epistemological, methodological or ethical pluralism have been acknowledged as intricate problems by some researchers who also embraced William James’s vision of pluralism as an important inspiration for a psychological understanding of the particularities of human existence (Araujo & Osbeck, 2023). Apart form a few attempts to allow for theistic interpretations of religious/spiritual experiences (e.g. Slife & Reber, 2021) the challenges of studying religious pluralism as described by Berger (e.g. 2014) and Woodhead (e.g. 2016) including the particularities of religious/spiritual experiences have not elicited a comparable response to the work of William James in the psychology of religion. This contribution aims to demonstrate that William James offers a valuable methodological and theoretical approach to religious pluralism. A close reading of (‘Introduction’ to) The Literary Remains of the Late Henry James (1884), The Will to Believe (1897), The Varieties of Religious Experiences (1902), Pragmatism (1907) and A Pluralistic Universe (1909) reveals four main features apt to study the plurality of religious/spiritual experiences: 1.) A comparative-descriptive method related to methodological individualism, 2.) A combination of a stipulative definition of religion with a reconstructive circumscription of the divine, 3.) A typological approach to theorizing religion including an explanatory concept from psychology ( the subconscious self) as a hypothesis and 4.) A pragmatic concept of truth allowing openings to other disciplines. In addition, James’s approach will be discussed in the context of recent methodological suggestions for studying religious diversity related to migration and to conflict-centered perspectives.