Psychologists say don't expect your life to be happy all the time. I go with the philosophy that every day can't be tops. Life is not like that - it's up and down.

I'm happy every day.

Being more happy than not helps you get up every day.

I found what I was looking for at Langley. This was what a research mathematician did. I went to work every day for 33 years happy. Never did I get up and say I don't want to go to work.

I don't need to go every day and re-evaluate, 'Am I living up to this? Or that or this?'

It's the ultimate goal every day you wake up, to be happy. At the end of the week, you want to be happy. Happy in love, happy in work, happy in life, happy with yourself. It's pretty simple.