Recent work has clearly established the fundamental place of the siddhis in almost all Indic mokṣa traditions. This paper seeks to excavate a fundamental metaphysical dimension to this phenomenon, by excavating the philosophical logic of these claims from within the contours of Sāṃkhya metaphysics as expressed in the Yoga Sūtras of Patañjali. It will set out to provide a coherent explanation of how these siddhis are not only an inherent ingredient of yogic discourse, but a logical and perhaps inevitable corollary (...) of the parameters of this metaphysics. It will thus take the issue further than a mere recognition of the centrality of the siddhis to yogic practice and discourse by laying out the sequential metaphysics underpinning them, and hence arguing that siddhis are not only fundamental and intrinsic to the Sāṃkhya/Yoga tradition, but an essential by-product of its metaphysical presuppositions. (shrink)