There are many excellent descriptions of the INTp (Intuitive Logical Introvert) out there, so I'll try to refrain from a rehash of all of those articles. But I'd like to take this opportunity to provide some of my personal observations of the type and how to know if you're in the presence of one.
- The INTp is intelligent. They possess great capacity for analysis, fact retainment, and rationalization. They have a reputation for being [objectively] critical. They have active imaginations and have a tendency to daydream, but they easily apply their powers of analysis to practical matters (an effect of extraverted logic).
- The INTp is outwardly confident. They are well-spoken and, when they choose to be, can be quite sociable. They love to discuss a variety of matters ranging from technology to spirituality and are quite capable in debate.
- The INTp is guarded. They are aloof and confide in very few people, preferring to keep an emotional/psychological distance. While outwardly confident, they are sensitive and prone to self-doubt, especially with regard to emotional matters.
- The INTp is sluggish. They have a calm and measured approach to almost everything and are not easily provoked, often using irony or humor to soften a tense situation. In their most natural state, they are constantly observing people and things, processing the information in order to increase their understanding.
- The INTp is detail-oriented. In relation to points #1 and #4, the INTp tries to observe every detail in order to have a complete understanding of a situation--this applies to their work, their hobbies, and their relationships.
- The INTp [generally] has a small frame and wears well-fitting but unremarkable clothes. This is true of males and females. Many INTp's have a proportionally large nose and will most often have a sullen or gloomy expression on their faces.