This is a simple but profound statue that I think shows a great deal of truth:
Only you can change yourself.
On the other hand, here is a quote by a man I admire:
In this case, I must disagree. My beliefs were based on evidence, and I was able to be convinced they were wrong. However, it is true for many people. If you don’t care about whether your beliefs are true, I cannot respect you.
The Complete History of the Universe: A Personal Journey 