If you're not stubborn， you'll give up on experiments too soon. And if you're not flexible， you'll pound your head against the wall and you won't see a different solution to a problem you're trying to solve.
Life lessons will be presented to you in the order they are needed. Everything you need to master the lesson is within you. Once you have truly learned a lesson， you will be presented with the next one. If you are alive， that means you still have lessons to learn.
