How does Chapter 4 contrast the effects of Sai's yogic presence with a philosopher's stone?

Chapter 4 draws a compelling comparison between Sai, the "Lord of Yoga," and a philosopher's stone. While a philosopher's stone, or Paris, is known for turning iron into gold, the text states that the action of a saint like Sai is "even more extraordinary." This is because through his yogic presence and teachings, he gives his own form, which is Self-realization, to his devotees. This transformation is far more profound than a mere material change, as it involves elevating a person to the supreme state of oneness where they realize their true nature as Brahman, a state of supreme devotion.