The most difficult subjects can be explained to the most slow-witted man if he has not formed any idea of them already; but the simplest thing cannot be made clear to the most intelligent man if he is firmly persuaded that he knows already, without a shadow of doubt, what is laid before him.
 Leo Tolstoy, The Kingdom of God Is Within You (1894). copy citation

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Author Leo Tolstoy
Source The Kingdom of God Is Within You
Topic doubt shadow
Date 1894
Language English
Reference
Note Translated by Constance Garnett
Weblink http://www.gutenberg.org/cache/epub/4602/pg4602-images.html

Context

“And the reason of this conviction is that the false interpretation and consequent misapprehension of the Gospel is an error of such long standing. Even the strongest current of water cannot add a drop to a cup which is already full. The most difficult subjects can be explained to the most slow-witted man if he has not formed any idea of them already; but the simplest thing cannot be made clear to the most intelligent man if he is firmly persuaded that he knows already, without a shadow of doubt, what is laid before him. The Christian doctrine is presented to the men of our world to-day as a doctrine which everyone has known so long and accepted so unhesitatingly in all its minutest details that it cannot be understood in any other way than it is understood now.” source