Youth is happy because it has the ability to see beauty. Anyone who keeps the ability to see beauty never grows old.
- Attributed to Franz Kafka, but source unknown
Anyone who stops learning is old, whether at twenty or eighty. Anyone who keeps learning stays young. The greatest thing in life is to keep your mind young.
- Henry Ford (1863 - 1947)
Keep the flame of curiosity and wonderment alive.
- Michio Kaku, an American theoretical physicist, in an interview