The word tantram is significant herein. Sometimes tantram is misunderstood to be the black spiritual science of materialistic persons engaged in sense gratification, but here tantram means the science of devotional service compiled by Śrīla Nārada Muni. One can take advantage of such regulative explanations of the path of devotional service and make progressive advancement in the devotional service of the Lord. Sāṅkhya philosophy is the basic principle of acquiring knowledge, as will be explained by the sage Maitreya. The Sāṅkhya philosophy enunciated by Kapiladeva, the son of Devahūti, is the real source of knowledge about the Supreme Truth. Knowledge not based on the Sāṅkhya philosophy is mental speculation and can yield no tangible profit.