K completes the great analysis by running buddhi (intellect/judgment), dhṛti (firmness/resolve) and sukha (happiness) through the three strands. Intellect (18.30–32): sattvic buddhi knows rightly what to do and not do, what to fear and not fear, bondage and liberation; rajasic buddhi confuses right and wrong, dharma and adharma; tamasic buddhi, wrapped in darkness, takes adharma to be dharma and sees everything upside-down. Firmness (18.33–35): sattvic dhṛti is the unwavering steadiness that holds mind, breath and senses in Yoga; rajasic dhṛti clings, with attachment, to duty, pleasure and wealth, craving their fruit; tamasic dhṛti is the stubbornness that will not let go of sleep, fear, grief, despair and conceit. Happiness (18.36–39): sattvic sukha is “like poison at first and nectar in the end”, born of the serenity of Self-knowledge — hard at the outset, blissful at maturity; rajasic sukha is “nectar at first, poison in the end”, born of the contact of sense and object; tamasic sukha, deluding from beginning to end, springs from sleep, sloth and heedlessness. This last triad is a jewel of practical wisdom: the worthwhile joys cost effort up front and reward later (the discipline of 6.16); the cheap joys reward instantly and cost dearly after; the worthless ones are pleasant only to a dulled mind. By this test alone one can sort one’s own pleasures.