If we were never troubled by how phenomena in the sky or death might concern us, or by ourfailures to grasp the limits of pains and desires, we would have no need to study nature.
I found this passage interesting because it alludes to the natural human instinct to investigate things that either confuse or more accurately, scare them. Fear or "concern" as stated in the passage, is a very strong driving force for innovation, and when coupled with a desire to "grasp the limits of pain and desire" is almost an unstoppable force when it comes to study and discovery. Without this intrinsic drive to learn and overcome mental insufficiency in regards to the world, human life would be stagnant and non-changing. I just think it is a cool way to look at human motivation to learn more about the world around us.