Chapter 2: Sankhya Yoga
the eternal self and steady wisdom
Krishna's teaching proper begins here, at verse 11. He tells Arjuna that the wise do not grieve, because the self is not born and does not die; only the body changes. He then introduces acting without clinging to the result, and describes the steady mind of a person who is not thrown around by pleasure and pain.
Separate what you control, your effort, from what you do not, the outcome.