A lot of people say they do drugs to "expand their mind." They say things like, "Doing drugs shows you there is more than one way to see reality."
Fine. But all you had to do to figure out that there is more than one way to see reality is read about another culture. Example: in some cultures, cows are sacred. In America, they're hamburgers. All you had to do was Google it. No need to kill brain cells. If you're going to do drugs to expand your mind, you should at least consider cutting up your coke with a library card.
The main thing you learn from doing drugs is not to do drugs.