It depends on what is meant by "good". A person with a 140 I.Q. is about 99% brighter than the rest of the population. However, socially it might prove disadvantageous. People with high functioning autism (such as Asperger Syndrome) can have an above average I.Q. and some people with that I.Q. might never get the encouragement they need to reach their potential. An I.Q. of 140 can be a blessing and a curse.