According to Osho, neither optimism nor despair begins yoga; it starts only when you drop the entire coin of hope and hopelessness. Total hopelessness means no expectation remains—not even the feeling of being hopeless—so the mind stops projecting a future. Free of clinging to hopes or miseries, you settle in present stillness; only then does Patanjali's Now, the discipline of yoga, truly begin.
Yoga starts when you stop hoping for the future or clinging to your sadness and just rest fully in the present.