To Live Among Friends Is

I Can Never Satisfy Myself Until I Can Make A Mechanical Model Of A Thing. If I Can Make A Mechanical Model, I Can Understand It. As Long As I Cannot Make A Mechanical Model All The Way Through I Cannot Understand.

I Often Say That When You Can Measure What You Are Speaking About, And Express It In Numbers, You Know Something About It; But When You Cannot Measure It, When You Cannot Express It In Numbers, Your Knowledge Is Of A Meagre And Unsatisfactory Kind.

Can You Measure It? Can You Express It In Figures? Can You Make A Model Of It? If Not, Your Theory Is Apt To Be Based More Upon Imagination Than Upon Knowledge.

I Have Not The Smallest Molecule Of Faith In Aerial Navigation Other Than Ballooning, Or Of The Expectation Of Good Results From Any Of The Trials We Heard Of. So You Will Understand That I Would Not Care To Be A Member Of The Aeronautical Society.

To Measure Is To Know.