Mankind is not a circle with a single center but an ellipse with two focal points of which facts are one and ideas the other.
Architecture has recorded the great ideas of the human race. Not only every religious symbol, but every human thought has its page in that vast book.
The man who does not know other languages, unless he is a man of genius, necessarily has deficiencies in his ideas.
The ideal and the beautiful are identical; the ideal corresponds to the idea, and beauty to form; hence idea and substance are cognate.
Thought is the labor of the intellect, reverie is its pleasure.
There is nothing as exciting as an idea whose time has come
Does there exist an Infinity outside ourselves? Is that infinity One, immanent and permanent, necessarily having substance, since He is infinite and if He lacked matter He would be limited, necessarily possessing intelligence since He is infinite and, lacking intelligence, He would be in that sense finite. Does this Infinity inspire in us the idea of essense, while to ourselves we can only attribute the idea of existence? In order words, is He not the whole of which we are but the part?
Ideas can no more flow backward than can a river.
The persistence of an all-absorbing idea is terrible.
A fixed idea ends in madness or heroism.
Every idea must have a visible enfolding.
Wide horizons lead the soul to broad ideas; circumscribed horizons engender narrow ideas; this sometimes condemns great hearts to become small minded.Broad ideas hated by narrow ideas,-this is the very struggle of progress.
You have enemies? Why, it is the story of every man who has done a great deed or created a new idea.
A day will come when markets, open to trade, and minds, open to ideas, will become the sole battlefield.
When you get an idea into your head you find it in everything.
One resists the invasion of armies; one does not resist the invasion of ideas.
One cannot resist an idea whose time has come.
A stand can be made against invasion by an army; no stand can be made against invasion by an idea.
A day will come when there will be no battlefields, but markets opening to commerce and minds opening to ideas.