महाभारत - अरण्य

व्याधेरनिष्टसंस्पर्शात् श्रमादिष्टविवर्जनात् ।
दुःख चतुर्भिः शारीरं कारणैः संप्रवर्तते ॥

- महाभारत, अरण्य

vyAdhiH aniShTa samsparshAt shramAt iShta vivarjanAt ।
duHkham chaturbhiH shArIram kAraNaiH sampravartate ॥

- mahAbhArata, aranya

Physical pain is caused by four stimuli - disease, bad luck, exhaustion (over working) or by separation from something you love.

- Mahabharata, Aranya