My mom didn’t discourage me from using drugs the way that most parents do.

She never gave me or my brother “the talk” about drugs or alcohol. Don’t get me wrong; she unmistakably disapproved of any kind of substance use and she cared deeply about our well-being. Her only half-joking tagline was: “Alcohol, cigarettes, and marijuana don’t kill gradually — they kill immediately because I’ll kill you as soon as I find out.”

She would ask if there would be alcohol before we headed out to parties, and she earned a reputation as the “human ankle bracelet” for her keen ability to keep tabs on where we were going. But my brother and I were never lectured about drugs the way many of my friends were.

Instead, over the course of many years, she ingrained in us her philosophy about how we drive our own destiny. According to my mother, life is like a long hallway. When you’re young, all the doors in the hallway are wide open. You can become a Princeton valedictorian, or a neurosurgeon, or start a successful business. You can be whatever you’re willing to work for. But as life goes on, you’ll make choices – and those choices will undoubtedly end up closing doors. A few doors may be closed for you by circumstance (at 5’7” and 135 lbs I was never going to be a football player), but the vast majority of your doors can only be closed by you.

At the core of her philosophy are freedom and responsibility. My mother gave us the freedom to make many of our own choices. I was never forced to study or to do my homework. Instead, my mother invoked her philosophy against my own personal goals. I was a competitive student, and she noted that watching TV rather than studying would slam the door on my chance of admission at an Ivy League school. And so I didn’t study just because she ordered me to; I was motivated to study hard to keep that door from hitting me in the butt.

Even before my brother and I were teenagers, my mother clearly explained to us that using drugs and alcohol would shut many of our doors. She offered examples: an underage drinking citation could close the doors to some colleges; a mind muddied by the effects of pot or other drugs might lead to bad grades and bad decisions that would, in turn, close other doors; and a body that reeked of cigarette smoke might close the door to potential dating partners.

What’s interesting about this technique is that my mom put virtually no emphasis on health effects. My brother and I were young kids, and she knew that, at that age, we couldn’t care less about the long-term health effects of drugs, drinking, or smoking. Right or wrong, most young kids just aren’t thinking about those things. If the only thing I had been warned about substance use in high school was that it was bad for my health, it would have been a lot easier to succumb to the pressure to give it a try. After all, I know Twinkies are bad for me – but I still eat them.

Instead, my mother focused on the things I cared about – my own goals and all those doors that I desperately wanted to keep open. I knew I wanted to accomplish something great one day – as a lawyer, a businessman, or an economist – and if avoiding dugs and alcohol was necessary to keep those doors open, I would do it.

My mother’s philosophy successfully kept me and my brother motivated and on track for success. Even more importantly, it helped my brother and me to take personal responsibility for our actions – because we could only blame ourselves when a door closed.