People have been asking me what the difference was between a Myers-Nriggs (MBTI) INTJ personality and a ESFP personality. Here is just a few examples of the differences. You can find tons more online.
Ideas come easily to INTJs. Not only do they understand unfamiliar concepts quickly, but they tend to form their own creative ideas and solutions to problems. This tendency is consistent with this type's appreciation for theory. In effect, while others around them may observe a problem and struggle to produce a potential solution, INTJs will often devise several possible resolutions. In fact, they will frequently eschew the obvious and simple solution for one that is more complex or even paradoxical. INTJs are generally highly intelligent and analytical.
The attributes that guide ESFPs throughout their lives carry inherent weaknesses that can either lead to problems or pose them directly. Their inclination to live their lives without planning can expose them to unfavorable circumstances. When stress emerges, an ESFP - accustomed to seeing life through a positive lens - will typically experience more emotional distress than others. In the end, as with all personality types, ESFPs must find a balance that allows them to leverage their strengths while minimizing their weaknesses.