" When the senses contact sense objects, a person experiences cold or heat, pleasure or pain. These experiences are fleeting; they come and go. Bear them patiently, Arjuna. 15 Those who are unaffected by these changes, who are the same in pleasure and pain, are truly wise and fit for immortality. Assert your strength and realize this! "

― Krishna-Dwaipayana Vyasa , The Bhagavad Gita