What is the "ordinary person" standard for determining whether a plaintiff acted in good faith and to the best of his own judgment?

In my view, the test that must be applied is the ordinary person standard. This standard has deep roots in the law. In Vaughan v. Menlove, (1837) 3 Bing. (N.C.) 468, Tindal C.J. dealt with a submission that a man whose intelligence was less than average and whose conduct led to the occurrence of a fire, should be judged by the standard of acting in "good faith" and to "the best of his own judgment." Tindal C.J. rejected this argument and said at p. 475: Instead, therefore, of saying that the liability for negligence should be co-extensive with the judgment of each individual, which would be as variable as the length of the foot of each individual, we ought rather to adhere to the rule which requires in all cases a regard to caution such as a man of ordinary prudence would observe.