We all have our addictions. Being automatically prejudiced against one that happens to shorten your life isn't as useful as realizing you may be addicted to something far worse, e.g. spending most of your time thinking about dating or worrying how to shape yourself to fit the die that some institution has cast for your life, like college or work.
Take the idea of evolution. As pg points out in his essay, the reason evolution was so difficult for people to accept is that species seem to be unchanging, static fixtures. It would be absurd to suggest that a dolphin used to walk around on land, yet evidence shows that they did, a couple million years ago.
It turns out that the idea of evolution is useful in other contexts. Most of the best software was written by following a procedure strikingly similar to how a creature evolves. The idea of "release early, release often" is the idea of evolution applied to the process of writing software. In fact, this idea is so valuable that we probably wouldn't be having this conversation without it, because neither Viaweb nor Arc nor YC would exist.
It was normal for society to be unaware of evolution the same way we're unaware of the spin of the Earth. And when people started to look at the evidence, it was normal for society to reject it. It wasn't until Darwin, an established scientist near the end of his life, that society allowed the idea to take hold.
The consequence is that those who live a life that society lays out for them are almost universally denied access to the best ideas, because the best ideas are the ones you haven't thought of yet.
It's tempting to believe that you're resistant to the effects of society laying out a normal path for you to follow. Aren't we free to think whatever we want? After all, no one can prevent us from thinking, right? Actually, that's exactly what happens. "Here is where you live. Here is where you play. Here is where you learn. Here is where you work. These are the hours you may relax." That cycle is too powerful to resist unless you actively try to break it. It stamps its seal onto your brain. For 16 hours a day, your thoughts are not your own -- they are owned by whomever pays you. The reason is because even though you are technically free to think whatever you want whenever you want, most people never do. At work, people think about work, or about coworkers. At school, you think about school or (more commonly) about other students.
That sounds quite a lot like an addiction. In the same way a drug user becomes obsessed with acquiring their fix, most people are obsessed with living whatever life society tells them to be living. And in practice that means most people are limiting themselves to a small fraction of their potential, because your potential stems from your ideas, and your ideas come from your thoughts, and your thoughts are mostly not your own.
I believe those addictions are the real ones to be avoided. And avoiding smoking is good while you're at it, but probably doesn't matter as much.
This is a strange defense. You are basically defending an addiction by saying that it is better than smoking crack or doing heroin. That doesn't really defend your addiction, it is just comparing it to other things you could do that would be even worse.
I don't really care if you smoke or whatever, it is just rather expensive in the short term and potentially outrageously expensive to the point of bankruptcy in the long term. Also there are shorter term health implications that kind of suck as well. It is certainly not a good investment.
