What is sthitaprajna, the person of steady wisdom, in the Bhagavad Gita?

Sthitaprajna (from sthita, "steady," and prajna, "wisdom" or "insight") is the Bhagavad Gita's term for a person whose understanding no longer wavers with circumstance. The concept appears in Chapter 2, verses 54-72, when Arjuna, having just heard Krishna's teaching on the imperishability of the soul and the idea of desireless action, asks directly: "What are the marks of one whose wisdom is steady, situated in samadhi? How does he speak, how does he sit, how does he walk?" (2.54). Krishna's answer runs for eighteen verses and is one of the most frequently quoted sections of the entire text. Krishna describes the sthitaprajna as someone who "casts away all the desires of the mind" and finds satisfaction in the self alone (2.55); who remains undisturbed in sorrow and unattached amid pleasures, free from attachment, fear, and anger (2.56); who withdraws the senses from their objects the way "a tortoise withdraws its limbs into its shell" (2.58); and who is unmoved equally by honor and dishonor, praise and blame, heat and cold. The mechanism Krishna gives for how this steadiness is reached is control over the senses: when a person dwells on sense objects, attachment arises; from attachment comes desire; from frustrated desire comes anger; from anger, delusion; and from delusion, the collapse of memory and reason, which Krishna calls total ruin (2.62-63). The passage ends with the well-known line describing this state as "the night of all beings" in which the disciplined person is awake, and what is waking for other beings is night for the sage who sees (2.69), before Krishna names this final state brahmi sthiti, "the state of Brahman," and says that whoever attains it even at the moment of death is freed (2.72). The sthitaprajna passage is often read as a self-contained ethical portrait, and Mahatma Gandhi is widely reported to have recited it as a personal discipline, but in context it directly answers Arjuna's practical question of how someone with steady judgment actually behaves, moment to moment, under pressure.