"When the weight of the paper equals the weight of the airplane, only then you can go flying"

This quote by Donald Wills Douglas is a metaphor for the significance of preparation. It recommends that before one can start a journey, they must first ensure that they are adequately prepared. The paper in this metaphor represents the preparation that must be done prior to one can go flying. The aircraft represents the journey itself. The quote implies that a person should make the effort to guarantee that they have done all the required preparation prior to they can embark on their journey. It is only when the weight of the paper, or the preparation, is equal to the weight of the plane, or the journey, that a person can go flying. This quote is a pointer that one should make the effort to prepare for their journey in order to ensure a successful outcome.