I could be biased, but I think NFs over all are the most intelligent. the reason I think NFs are as a whole more intelligent than NTs is because our intuition is less inhibited. NTs can grasp theoretical concepts better than most types, but they often have trouble understanding more subjective concepts and sometimes miss things that NFs pick up immediately. my INTJ friend is a total mastermind at business, economics and strategy, but he misses some of the most obvious things because he has a harder time understanding things until he breaks them down and restructures them into an objective model. he is only recently discovering the limits of what is objectively provable and the value of grasping information subjectively in order to understand it more quickly. however, I believe NTs have the most "practical intelligence" of the archtypes. they are by far the most likely to earn a high income and they have a nack for taking complex theory and applying it in a practical and strategic way. they also tend to be better at focusing intuition and thinking toward understanding a highly leveraged skill, systemizing it and optimizing it so that they become extremely proficient at a profitable skill in a short amount of time.