This critical reference work offers an exhaustive study of the major ideological paradigms of the twentieth century. It comprehensively unpacks the distinct spiritual and humanist systems introduced by spiritual masters and leaders, including Swami Vivekananda, Rabindranath Tagore, Mahatma Gandhi, and Sri Aurobindo. Furthermore, the book evaluates complex metaphysical structures from academic philosophers like Krishna Chandra Bhattacharya, Sarvepalli Radhakrishnan, and Sir Muhammad Iqbal. Readers seeking deep intellectual insights can find related classical titles in our Contemporary Indian Philosophy Books corner. This handbook condenses intricate theoretical structures into accessible insights, making it a valuable asset for research scholars.