The data showed that although an observer is no more "sensitive" to gain in efficiency than he is to loss, he is predisposed to judge both himself and another performer whom he is watching as having done "better than usual" rather than "worse than usual." The consequence is that smaller degrees of superiority tend to be judged as better with higher degrees of confidence, and that a certain slight degree of inferiority tends to be incorrectly judged as "better." We seem predisposed to judge "better" rather than "worse," and in this experiment the observers were, furthermore, predisposed in favor of the other person, somewhat more than in favor of themselves. They were disinclined to judge any trial as "worse than usual," and this disinclination was stronger when judging as witness than when judging as performer. This results in a combination of altruism and optimism which, if found to be a common occurrence, would seem to have interesting implications. Further investigation will perhaps show that these attitudes are conditioned, under different circumstances, by a variety of factors, such as competition, education, motive, age or sex of performer and witness, and perhaps by individual differences of a temperamental sort.
When Cattell had scientific men arrange their colleagues and themselves on the basis of scientific merit, he found no constant tendency either to overestimate or to underestimate oneself. He remarks, concerning this result: "It thus appears that there is no constant error in judging ourselves--we are about as likely to overestimate as to underestimate ourselves, and we can judge ourselves slightly more accurately than we are likely to be judged by one of our colleagues. We can only know ourselves from the reflected opinion of others, but it seems that we are able to estimate these more correctly than can those who are less interested. There are, however, wide individual differences; several observers overestimate themselves decidedly, while others underestimate themselves to an equal degree."[11]
Since these individual differences, in all the investigations that have been reported, are so conspicuous, we may next inquire whether the individual who possesses a given trait in high degree is a better or worse judge of that trait in himself and in others, than is a person in whom the trait itself is less marked.