INTp's main function is introverted intuition (
). Since introverted intuition is about internal wholeness or belief, this manifests itself in INTps being highly religious and spiritual people. It is also their area of confidence and conservatism and they will not welcome anything that could disturb that internal wholeness. And since you can believe in things that are not necessarily there or actually true, INTps criticise a lot. As for INTjs, their intuition is their second strong function, which is extroverted intuition (
). Extroverted intuition is about perspective and potential and because it is INTj's creative output, their "creations" could be very unexpected and original, often bearing a high potential for future development. So, combining two and two together, INTjs are in their element when involved with science, invention, innovation, discovery, theory, explanation, interpretation, philosophy etc. INTps are in their element when involved with business, enterprise, commerce, industry, trade, financial institutions, church etc.