The book deals with three landmarks of Samkhya philosophy, the oldest of the Indian philosophical systems. The first, the aphorisms of Panchashikha etc. are fragmentary remains of compositions by the sages in the Upanishadic era; the second, Ishvarakrishna's Samkhya-Karika,
possibly the first Indian philosophical text to gain appreciation abroad; the last one, the author's Samkhya-tattvaloka was first published in 1903. Interspersed with these are articles on allied topics and some illustrative appendices.