To be able to discern that ...

To be able to discern that what is true is true, and that what is false is false,--this is the mark and character of intelligence.
To be able to discern that what is true is true, and that what is false is false,--this is the mark and character of intelligence.

Quotes from the same author

Thought is the blossom; language the bud; action the fruit behind it.
The invariable mark of wisdom is to see the miraculous in the common.
Our distrust is very expensive.
Wisdom has its root in goodness, not goodness its root in wisdom.
Do not follow where the path may lead. Go, instead, where there is no path and leave a trail.