जातिलक्षणदेशैरन्यतानवच्छेदात् तुल्ययोस्ततः प्रतिपत्तिः || ५३ ||
Jāti-lakṣaṇa-deśair anyatā’navacchedāt tulyayos tataḥ pratipattiḥ III:53
“From this, one gains the ability to discern between two identical things that are not distinguishable by their outward characteristics.”
Patanjali and Vyasa argue throughout the Sutras that although knowledge of facts and knowledge gained from books can be useful, it is limited in that it can only tell you about the characteristics of categories of things. It can never tell you about the actual particularities of individual objects. So, you can learn that mammals have fur and breastfeed their young, you can even learn what distinguishes different *kinds* of mammals from each other, but this type of knowledge will never allow you to *fully* understand any unique individual instance of a mammal.
The claims to “powers” that are presented in the Yoga Sutras are neither mere peripheral things to gloss over (there are in fact a lot of Sutras devoted to speaking about them) nor are they meant to be ways of achieving worldly ends. Instead, they are guide posts that are meant to show that we have deeply understood and integrated a Yogic concept.
So, Patanjali’s claim that, through meditative practice, one gains the ability to discern between two identical objects, indicates that the Yogi has, at this point, transcended ordinary “book knowledge.” He or she is able to actually perceive things as they are and not merely as examples of a certain category or type. What were once just different examples of a kind of object are now seen in their full individuality.
This is illustrated creatively in the story of Gorakh’s rescue of Matsyendranath, where Gorakh produces 108 clones of Queen Mainakini and Matsyendra’s son Minanath. Gorakh asks the Queen to choose her real son and, when she is unable to do so, he says, “If you’re not able to recognize your own son, how can you call him yours?” (Munoz, Adrian. Matsyendra’s “Golden Legend”)