Yoga Sutra 1.46 samadhi from a seed
Sūtra I.46
These are samādhi from-a-seed
These four samādhi-identifications have external things as their seed, so the samādhi is from-a-seed (sa-bīja). When it is a physical object, the samādhi is sa-vitarka or nir-vitarka; when a subtle object, it is sa-vicāra or nir-vicāra. So the four categories of samādhi have been described.
They are from-a-seed because their objects are external things. The samādhi is from-a-secd, namely cognitive, as was explained under sūtra I.17: ‘cognitive because accompanied with verbal associations (vitarka), subtle associations (vicāra), joy (ānanda), and the form of I-am-ness (asmitā)’. When it is a physical object, the samādhi is sa-vitarka or nir-vitarka: when a subtle object, it is sa-vicāra or nir-vicāra. So the four categories of samādhi have been described.