"I have learned to use the word "impossible" with the greatest caution"

Wernher von Braun's quote is a reminder to be careful when utilizing the word "impossible". He is suggesting that we ought to not be so quick to label something as impossible, as it may be possible with the correct amount of effort and dedication. He is motivating us to think outside package and to not be discouraged by the concept of something being impossible. He is also suggesting that we ought to not be so fast to quit on something just because it appears difficult. Instead, we must put in the time to check out all possibilities and to think about all options prior to quiting. By doing this, we may have the ability to discover a way to make the difficult possible. Von Braun's quote is a tip to be open-minded and to never quit on our dreams, no matter how impossible they might seem.