Wise men put their trust in ideas
and not in circumstances
- Ralph Waldo Emerson
I can't understand why people
are frightened by new ideas.
I'm frightened of old ones.
- John Cage
There are no constraints on the human mind,
no walls around the human spirit, no barriers to our
progress except those we ourselves erect.
- Ronald Reagan
The difficulty lies not so much in developing new ideas
as in escaping from old ones.
- John Maynard Keynes
The world moves, and ideas that were
once good are not always good.
- Dwight D. Eisenhower
Incite a riot of new ideas.
- Jonathan Lockwood Huie
An invasion of armies can be resisted,
but not an idea whose time has come.
- Victor Hugo
Further reading: A Better Plan
Choice vs. Conformity
Flexibility
Progress