The Dasa Indriya or ten senses of experience and action,
whilst seen as belonging to the Bāhya Aṅga or five external limbs
in the eight limb Aṣṭa Aṅga Yoga of Patañjali,
are also the gateway to the Antar Aṅga or three internal limbs.
– Yoga Sūtra Chapter Two verse 54

Link to Series: 108 Sutra Study Pointers