No, you don't understand what you're doing. That is the only reason it would be best for you not to do it. I'll give you an example.

"I'm doing weed because it makes me feel good."

"I'm doing weed because it's cool to do it."

"I'm doing weed because it's fun."

"Even though weed fucks me up at school, I still do it because I want to feel good."

"Even though weed makes my parents angry, I still do it because I like it."

All of the above statements and probably any more you can think of are cases of not understanding what you are doing. Somebody who understands what they are doing would think the whole thing through and destroy their negative feelings about it, or come to the conclusion that they are going to stop it:

"I am doing weed because it alters my perceptions in a way that I find interesting. I understand it will most likely cause memory loss, lung cancer, decreased sperm count, could possibly cause mental problems, and is expensive. I also understand that there may be other problems I am not aware of that could arise from it. These things, to me, aren't necessarily problems. I am going to die, I have already lived, and I am willing to accept death at any moment. Many people may not understand my choice, they may think lowly of me, I forgive them. I understand their choices, their decisions are completely valid.

Weed may affect my education and future career. I am OK with that, since I can see through the false priorities society has created. For practical purposes, I will pursue a career like everyone else, but I realize that it is not important for my happiness.

Everybody around me is going to die, my relationships with them are impermanent. Any pain in them caused by me is a result of misunderstanding, so it is alright if weed affects my relationships. Though, I am sorry they had to feel that way, and I will do my best to liberate them from their suffering because I love them.

Weed is not necessary for my happiness, I don't need to do it. I realize that it is impossible for weed to really stop any of my suffering or really grant me true happiness.

I am happy with doing weed. I see that all the negative effects I thought it had were actually illusions, my guilt and desire to stop doing it have disappeared, and I feel completely content."

The above statement shows how somebody who understands what they are doing would deal with their "problem." This is just one example, it could have gone the other way and ended with "I will stop doing weed, and I am completely content with stopping." And there would be no conflicting desires in that case either. I know it's pretty long, usually all of that dialogue would be condensed into a few feelings or thought processes or something.

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