By samyama knowledge of other’s mind
3.19. Pratyayasya parachittajnanam|
- Pratyayasya-of the content of the mind
By practicing samyama on the pratyayas, knowledge of others mind known.
But not mental image
3.20. Na tat salambanam tasyavisayibhutatvat|
- Salambanam-with support
- Avisayibhutatvat-because of not being the subject of samyama
But the knowledge of other mental factors is not gained with support of the mental image because that is not the object of samyama.