If I had wished to present my readers with nothing but a dry chronicle of facts I should have toned this down to something more prosaic.

But every one who has had any experience of life will know that her surprises are sometimes very bewildering; that fiction is nothing but uncommon experience made ordinary, or heaped inartistically upon a single character.
It may be said that the man was mentally affected, in the latter scene; in the former, that Arthur himself was the victim of a mental disorder; but he left such vivid and detailed descriptions of both events that I have been enabled to give one (the letter) exactly as it stands, and the interview in Teheran is taken directly from diaries--a little amplified and reconstructed, it is true, but only when interpreted by the light of later events.
And this must be always the task of the true biographer; for the biographer has to take a life _en masse_, and disentangling the predominant and central threads, cast the rest away; in this process rejecting facts and incidents whose isolated interest is often greater than the interest of what he retains, because it is on the latter that the pearls of life are, so to speak, strung.
In this case the two incidents I have kept are both so pregnant of influence upon his later life, so necessary to the logical development of his principles, that, in spite of their romantic, not to say wild, character, I have retained them..