The Book of General Ignorance round differs, in particular during the Christmas specials. During the course of the "B" Series special, Fry and Davies swapped places for "General Ignorance", with Fry attempting to answer questions ostensibly written by Davies to stump him. During "D"s Christmas Special, all the "GI" questions revolved around saints. "The Book of General Ignorance" contains a list of 230 questions, most of which previously appeared in episodes of "QI". Each question explains the correct answer, and usually attempts to show why people tend to make the wrong assumptions, or believe certain myths. Each book contains two forewords, one by Fry, the
All-or-none law contraction is not increased if the stimulus strength is further raised. Stronger stimuli bring more muscle fibres into action and thus the tension of a muscle increases as the strength of the stimulus applied to it rises. All-or-none law The all-or-none law is the principle that the strength by which a nerve or muscle fibre responds to a stimulus is independent of the strength of the stimulus. If that stimulus exceeds the threshold potential, the nerve or muscle fibre will give a complete response; otherwise, there is no response. It was first established by the American physiologist Henry Pickering Bowditch