How to gain liberation from duality?

The following is an excerpt from a samvaad (dialogue) session with Acharya Prashant.

Questioner: Acharya Ji, how to gain liberation from duality?

Acharya Prashant: By knowing that it is duality. Right now you are calling the ‘self-world relationship’ as dual but only right now. Ordinarily, you do not see it as a dual relationship.