Note 6 — Front matter

"Suppose a fact to be transmitted through twenty persons; the first communicating it to the second, the second to the third, &c., and let the probability of each testimony be expressed by nine-tenths, (that is, suppose that of ten reports made by each witness, nine only are true,) then, at every time the story passes from one witness to another, the evidence is reduced to nine-tenths of what it was before. Thus, after it has passed through the whole twenty, the evidence will be found to be less than one-eighth."—La Place, Essai Philosophique sur les Probabilités.

That is, the chances for the fact thus attested being true, will be, according to this distinguished calculator, less than one in eight. Very few of the common newspaper-stories, however, relating to foreign countries, could be traced, if the matter were carefully investigated, up to an actual eye-witness, even through twenty intermediate witnesses; and many of the steps of our ladder, would, I fear, prove but rotten; few of the reporters would deserve to have one in ten fixed as the proportion of their false accounts.