“The used key is always bright.”

“When the future looks dark, do not panic, because future does not exist yet; by using your intelligence, you can always turn it to bright!”

“A brick could be used as a key to unlock a door disguised as a brick wall. The security in the lock lies not with a one-of-a-kind key, but with a key that looks like hundreds of other potential keys that make up the door.
”

“Well, the family always was bright, and brightness, as you know, decays brilliantly.”

“A duodene of bird notes chirruped bright treble answer under sensitive hand. Brightly the keys, all twinkling, linked, all harpsichording, called to a voice to sing the strain of dewy morn, of youth, of love's leave-taking, life's, love's morn.”

“Vibrations are the key to everything. Atoms used to be, but atoms have quite gone out.”