"We were not looking for a fortune, but we were looking for a solution."

"If its engine stops, it must fall with deathly violence, for it can neither glide like the aeroplane or float like the balloon. The helicopter is much easier to design than the aeroplane, but is worth…"

"The fact that the machine did not fall apart at the first gust of wind was a great encouragement."

"We were lucky enough to grow up in an environment where there was always much encouragement to children to pursue intellectual interests; to investigate whatever aroused curiosity."

"If we worked on the assumption that what is currently accepted as true really is true, then there would be little hope for advance."