"We are tempted to believe that a slave can not possess it, inasmuch as it is the special possession of all those to whom riches give a superior position in the world.
"How profound is this error!
"The lowest slave can enjoy this liberty, which is worth all others: self-control, which confers intellectual independence more precious than the most precious of possessions, whereas the most powerful prince may be altogether ignorant of this blessing.
"There are dependent souls who, for want of the necessary strength to escape from vassalage to the external impressions will always drag on, feeble and opprest by the exactions of a mental servitude from which they can not free themselves.
"Others rise proudly, ready to command circumstances, which they dominate with all the power of their volition governed by reason.
"It is common sense which will guide them in this ascent by keeping them within the limits assigned to those things pertaining to reason and rectitude of mind.
"Before everything, it is well not to forget that this faculty invites those who cultivate it to seek always for exact facts.
"Knowledge, in all its aspects is, then, a perfect educator for those who do not wish to build on the flimsy foundation of approximate truth.
"In pronouncing the word knowledge, we do not wish to speak of abstract studies which are only accessible to a small number; we wish to express the thought of instruction embracing all things, even the most humble and ordinary.
"A man from the city was walking in the country one day, not far from a vast swamp.