Do you study old philosophers?
A bit, not as well as I would like. Who did you have in mind? Pre-Socratics?
The ancient Greeks like Epicurus who thought the key to a good life is to be free from pain.
I do know Epicurus. We get "epicurean" from his work, the enjoyment of sophisticated pleasures and the avoidance of pain. What can you tell me about the Stoics?
The Stoics believe we cannot rely on external events, but just ourselves and our responses.
Right. Who were the major proponent of Stoicism?
I am not sure but it is similar to Buddhism.
Who first formulated the philosophy? 
It was Zeno of Cittium who founded the Stoic school in 322 BC named after a lecture hall.
Zeno! OK, I'll have to look him up. I'm a bit familiar with Marcus Aurelius, I read his Meditations many years ago.