One of the key aspects of Eastern Philosophy is personal experience, not belief or faith in any certain principles.
One of the main appeals that Eastern philosophies and spirituality have for the intelligent and spiritually-minded Westerner is their more "mystical", "esoteric", and Monastic understanding of reality. For searchers after truth previously only allowed the sterile choice between Skeptical Materialism on the one hand, and dogmatic religious (theistic) Dualism on the other, this is a welcome choice.
Eastern monism has thus come to represent a third alternative for those who find Materialism and Monotheistic dualism options that are two shallow and limiting.
Historically, metaphysics in the Western (or Western and Middle Eastern) world has tended to maintain a tension between religion and secularism - between monotheistic religions like Judaism, Christianity, Islam, and Bahai'ism on the one hand, and philosophical and humanistic materialism and scientism in the modern world on the other. The philosophical and metaphysical distinction between dualism and materialism that has so much shaped Western thinking goes back to the ancient Greeks, Pythagoreanism and Platonism representing the dualist position, Atomism and Epicureanism the Materialistic, and Aristotleanism and Stoicism as a sort of holistic or quasi-holistic "third way" between the two. To some extent this is also the case in China as well, although not to so great an extreme.
In Chinese thought the metaphysical tension seems to be between Materialism and Monism, the result being a Holistic understanding of reality not as a hierarchy or a duality, but as the complementary play of the bipolar forces of yin and yang. Although China assimilated foreign religions and ideologies like Buddhism, Marxism, and most recently Consumerism, she has shown little inclination or interest in the theistic religions of other lands, perhaps because their rigidly dualistic nature is at variance with the intrinsic Chinese tendency to holism.
Since the Beatles' flirtation with Hindu Gurus like Mahareshi Yogi and Prabhupada in the late '60s, the presence and popularity of Indian spiritual teachers or Gurus has made a small but significant contribution to the religious consciousness of the West.
Lets hope that continues!