Soren Kierkegaard — "The highest of all is not to understand the highest, but to act upon it."

"The present age is essentially the age of understanding, of reflection, without passion, momentarily bursting into enthusiasm, and then shrewdly relapsing into repose."

"The self is a relation which relates itself to itself or, what is the same thing, is in the relation's relating itself to itself."

"The present age is essentially a sensible, reflecting age, which knows how to do everything, but which does nothing."

"The greatest danger, that of losing one's own self, may pass off as quietly as if it were nothing; every other loss, an arm, a leg, five dollars, a wife, etc., is sure to be noticed."

"The greatest danger in life is that you may take too many precautions."