Despite having no functions in common, the INTJ and INTP personality types often arrive at surprisingly similar worldviews. Since both types seek an understanding of themselves and the world, they can enjoy extensive discussions and find common ground on any number of topics. Whatever their similarities, INTJs and INTPs also differ in some important ways. Often times, these differences can seem subtle and require careful analysis to understand their origin. In this post, I hope to do just that, to get a better grasp on some key INTP-INTJ differences.
Outwardly, distinguishing INTJs from INTPs is generally not all that difficult. Since INTJs extravert their Thinking (Te), an outsider quickly encounters their rational nature. INTJs are articulate, measured, and direct in their speech. They see themselves as strong debaters and are undeterred in challenging those making dubious assertions about truth. It pains them to allow untruth to go unchallenged.
INTPs, on the other hand, extravert Intuition (Ne) and Feeling (Fe). These functions allow INTPs to blend more easily into social situations. Assuming they are not overly awkward or anxious, they may, at least initially, remain relatively undistinguished from other types. Because their Fe is inferior, INTPs tend to be far less comfortable directly challenging others’ assertions. INTPs are more selective when it comes to asserting their own views or displaying their rational side. They are disposed to posing questions or positing possibilities (Ne) rather than making strong assertions (Fe) in intellectual discussions.
Since their dominant function, Introverted Intuition (Ni), is a Perceiving function, INTJs are, first and foremost, geared to perceive information. As with INFJs, INTJs’ inferior Se unconsciously apprehends information about the outside world which their Ni then synthesizes into an “impression.” Ni gives INTJs a hunch about what is happening, whether good or bad, and can work at both broad and local levels. Broadly, Ni may give INTJs a sense of what is happening in the big picture of the world. Locally, it might provide insight for solving an immediate problem. The same is true for INFJs.
While the Se-Ni process is the same, INTJs and INFJs generally focus on different types of data. INTJs’ Se is drawn to Te information—physical systems, structures, processes, etc. INFJs’ Se is oriented to Fe information, that is, to the world of people. Because INTJs’ Se attunes to Te sorts of information, they are generally better equipped to solve T sorts of problems. Likewise, INFJs’ attunement to Fe data confers an advantage in understanding human nature and human problems. This is why, for example, INFJs are generally better suited to work as counselors than they are physicians, with the opposite being true for INTJs.
INTJs who were abused, mistreated, or whose Fi was otherwise deeply affected may also develop strong interests in F matters, especially understanding their own personal past. They may spend significant time trying to analyze their childhood, trying to make sense of what happened and understand who they are as individuals (Fi). In such INTJs, one can often trace a connection between their Fi feelings and their Te objectives. In many cases, the things that are most disturbing to INTJs, both to their Fi and Ni, are the things they hope to understand and remedy. So it is not merely shortcomings in rational systems (Te) that motivate INTJs, but also negative experiences or feelings (Fi). The degree to which Fi plays a role in a given INTJs’ concerns and interests will vary according to his or her experiences (This may also impact whether an INTJ scores as an Enneagram 5w6 (lower Fi involvement) or 5w4 (higher Fi involvement)).
Since both Ni and Te work convergently, INTJs are natural problem solvers. This is why they make excellent troubleshooters, consultants, analysts, mathematicians, physicians, scientists, and engineers. This is one way they differ from INTPs. INTPs can readily generate ideas or possible ways of addressing a problem a la Ti-Ne, but they are less apt to come to a firm conclusion about what is happening or what should be done. If someone wants a firm opinion or direct advice about a complex issue, they are far more likely to get it from an INTJ than from an INTP. This can make INTJs a better fit for the working world, since people tend to want firm answers rather than a litany of options.
Despite their knack for problem solving, INTJs may struggle to find their niche in the world because of their strong idealism and perfectionism. Some INTJs don’t just want to solve any problem, but the problems that have the biggest impact on the world at large. This is not necessarily a bad thing. If there is a personality type that can see the big picture and zero-in on its most pressing issues, it is probably the INTJ. An INTJ friend of mine is always talking about “leverage points.” His goal is to identify the key leverage points in the system, issues that he feels are the most foundational and play the largest role in the world’s problems. Their interests in such big picture issues may lead some INTJs to abstain from more ordinary career roles and function instead as outside analysts.
Once INTJs do discern what they see as key insights or leverage points, they may, at least for a time, function as advocates, activists, or reformers (This is why some INTJs also test as Enneagram Ones.). They may write about their insights, try to connect with and inform influential people, or even form interest groups or non-profit organizations. They may continue in such a role until they encounter what they see as insurmountable resistance or until they conclude there is likely a better way to effect change. INTJs’ drive to understand and change the world is exemplified in the life and work of my INTJ friend, Howard Ditkoff, who details his research, theories, and life experiences on his “systems thinker” website.
Since their dominant Judging function is directed inwardly (Ti), INTPs tend to be more interested in understanding themselves and finding wisdom than they are in directly changing the world. As is true for many INFPs, the self—its structure, nature, health, and identity—is a constant reference point for INTPs. While INTJs may display some of this because of their Introversion and their tertiary Fi, it is typically to a lesser degree. Since Te comes before Fi in their functional stack, INTJs are, wittingly or not, generally willing to sacrifice some degree of self-understanding (Fi) for the sake of working to improve the world (Te). This would be far more unusual for INTPs, who first priority is finding wisdom and self-knowledge.
Interestingly, I think this may explain where the notion of INTPs being interested in knowledge “for its own sake” originated. Since INTPs use their knowledge inwardly (Ti), others are largely blinded to the process, thereby leading them to assume the INTP a mere “idea hedonists.” But the fact is that INTPs do apply their knowledge, only they apply it primarily to understanding themselves, to finding their rightful place in the world, and to their quest for wise and optimal living. So the notion that INTPs are leisurely and aimlessly consuming ideas for mere pleasure completely misses the mark (In fact, this would probably be truer of INJs, whose dominant function is a Perceiving function.). Since Ti is a Judging function, INTPs tend to be quite intentional about what they do. This is why, for instance, they are insistent on efficiency and can be quite miserly about how their time is being used.
With this in mind, we can see how INTJs and INTPs work in different directions. INTJs focus in a more direct way on ways the world can be improved and, in the process, come to better understand themselves (Fi). INTPs, by contrast, focus first on understanding and improving themselves (Ti) and, in the process, hope to provide a roadmap for others to do the same (Fe). The way of the Buddha is in many ways characteristic of the INTP approach—figure out how to save yourself first, then help others do the same. In this light, the idea of grassroots or “bottom-up” change holds particular appeal for INTPs.
This is not to say that INTPs ignore what’s happening in the outside world (although they may be somewhat less concerned than INTJs are). Rather, they analyze it with an eye toward furthering their understanding themselves (Ti) and the human condition (Fe). Because INTPs have Fe rather than Te in their functional stack, their Ne is more drawn to exploring Fe sorts of information. This is why INTPs share much in common with INFJs (who also use Fe and Ti) and tend to be most captivated by things like philosophy, psychology, and religion. The T information INTPs do manage to collect (e.g., scientific or historical facts) is generally done in hopes of furthering their understanding of themselves and human nature.
While INTJs can excel in careers involving real-world evaluation and problem-solving, INTPs prefer work they feel is relevant to their quest for wisdom and self-knowledge. As explained in my recent post on the ideation of NP types, INTPs enjoy using Ne to make broad connection among ideas, an endeavor they find deeply interesting and meaningful. Again, their goal is not necessarily to solve the world’s problems (although this might occur indirectly), but to clarify concepts and conceptual relationships in a way that is personally meaningful and moves them closer to a sense of truth and coherence of thought. Like INFPs, INTPs enjoy weaving together disparate ideas into a meaningful synthesis. The primary difference is that INFPs are more apt to do so in works of art, poetry, music, or fiction, whereas INTPs dwell primarily in the world of concepts.