Rationalization = excusing your lack of success based on factors beyond your control, circumstance = accepting the factors beyond your control and playing the hell out of the factors that are in your control.

It's too bad that Marc Andreesen took his career advice blog post off the Internet, because he had some of the best advice I've seen. It was:

  1. Build skills & relationships.
  2. Take advantage of opportunities

Basically, all of the big leaps in your career will happen because some random big opportunity outside of your control will open up. When it does, jump on it. Immediately. Drop everything you're doing for it. Most people don't, and that is why most people slave away their lives in cubicles.

But to seize that opportunity, you need to be qualified, and you need to hear about it. So all the time that you're not actively seizing an opportunity, you should be building your skill base and getting to know other people. That's the important part: opportunities happen to everybody, but the vast majority of people aren't in a position to take advantage of them.

> I've never understood the difference between rationalization and circumstance.

Let's start there. Circumstance is a fact, rationalization is a story you tell yourself. Of course there is all types of rationalization and all types of stories. In this case though, your circumstance and your personal narrative are combining with a pessimistic quality. Pessimism is not always bad, it may be a good hedge against disappointment.

In this case you are taking it too far though. You could just as easily be telling yourself a positive story about your ability to execute on side projects while holding down a day job, or the fact that you are young and have low expenses, or that you are fortunate enough to be passionate about one of the few careers that's not shrinking these days, or even the fact that you won the birth lottery. It actually doesn't matter what you tell yourself though, as long as it helps maximize your potential. You could be the richest white kid in Beverly Hills or the poorest peasant in China, your attitude is the greatest thing you can control that can affect your circumstance. That doesn't mean the rich kid has much chance of being a billionaire or the peasant can reasonably hope to make $50k/year, but within their respective circumstances, attitude and action can make a world of difference.