Marijuana do not expand the mind, it kills the brain slowly. The sensation of freedom you feel when smoking it is the sensation of actual brain cells dying. Relief from life.
Wanna expand your mind?
Every second of the day stem cells are produced in your hippocampus, they usually die within a day or two. But - if you, with mental effort, which is key, learn new information and learn to entertain and explore perspectives that you not necessarily agree on, that will direct those stem cells with a task that means they will find a purpose and a place. Thus expanding the mind has been absolutely achieved.