na ca tat-sālambanaṃ tasya-āviṣayī-bhūtatvāt
[Whilst knowledge of others is acquired] not their foundation, because that is not the support of this Saṁyama
There is a limit to the power mentioned in Sutra III.19. Assuming you can know every other ‘self’, you cannot read their thoughts as such. What constitutes the very foundation of the thoughts of others is not accessible because it cannot be the object of Saṁyama.
Damian Cadman-Jones is an authorised teacher of Prana Vashya Yoga™