In his philosophy, What Is Man?, and now and again in his other writings, we find Mark Twain giving small credit to the human mind as an originator of ideas.  The most original writer of his time, he took no credit for pure invention and allowed none to others.  The mind, he declared, adapted, consciously or unconsciously; it did not create.  In a letter which follows he elucidates this doctrine.  The reference in it to the “captain” and to the kerosene, as the reader may remember, have to do with Captain “Hurricane” Jones and his theory of the miracles of “Isaac and of the prophets of Baal,” as expounded in Some Rambling Notes of an Idle Excursion.

     By a trick of memory Clemens gives The Little Duke as his suggestion
     for The Prince and the Pauper; he should have written The Prince and
     the Page, by the same author.

To Rev. F. Y. Christ, in New York: 

Redding, Conn., Aug., ’08.  Dear sir,—­You say “I often owe my best sermons to a suggestion received in reading or from other exterior sources.”  Your remark is not quite in accordance with the facts.  We must change it to—­“I owe all my thoughts, sermons and ideas to suggestions received from sources outside of myself.”  The simplified English of this proposition is—­“No man’s brains ever originated an idea.”  It is an astonishing thing that after all these ages the world goes on thinking the human brain machinery can originate a thought.

It can’t.  It never has done it.  In all cases, little and big, the thought is born of a suggestion; and in all cases the suggestions come to the brain from the outside.  The brain never acts except from exterior impulse.

A man can satisfy himself of the truth of this by a single process,—­let him examine every idea that occurs to him in an hour; a day; in a week —­in a lifetime if he please.  He will always find that an outside something suggested the thought, something which he saw with his eyes or heard with his ears or perceived by his touch—­not necessarily to-day, nor yesterday, nor last year, nor twenty years ago, but sometime or other.  Usually the source of the suggestion is immediately traceable, but sometimes it isn’t.

However, if you will examine every thought that occurs to you for the next two days, you will find that in at least nine cases out of ten you can put your finger on the outside suggestion—­And that ought to convince you that No. 10 had that source too, although you cannot at present hunt it down and find it.

The idea of writing to me would have had to wait a long time if it waited until your brain originated it.  It was born of an outside suggestion —­Sir Thomas and my old Captain.

The hypnotist thinks he has invented a new thing—­suggestion.  This is very sad.  I don’t know where my captain got his kerosene idea. (It was forty-one years ago, and he is long ago dead.) But I know that it didn’t originate in his head, but it was born from a suggestion from the outside.