Katie asked: My sister and I are both ENTP’s, our parents are an ENFJ and and ISTP. I wonder if this is an argument for nurture over nature, have you come across many siblings of the same type?
Yes, it happens a lot more often than you’d think. I know a pair of identical twins who both have the same personality types, same major in college, and the same interests. The only reason I can tell them apart is because I’ve known one of them longer and as a result, she’s more comfortable around me.
At the same time, I’ve also known sets of identical twins who are polar opposites of each other (where one was an ESFJ and the other was an ISFP).
More commonly, I encounter similar functions between children and their parents or grandparents. For example, my INTP rock-climbing friend has an INTP dad, or my ESFP brother’s INTJ best friend has an INTJ dad.
As for nature vs. nurture, I don’t think there’s a clear-cut line between where personality type is the result of nature and where it’s the result of nurture, but from my observations and readings it seems most likely that it’s a combination of the two.
The only other INTJ I know of in my family was my great-grandmother, and after she died, it was fascinating for me to help my grandparents sort out her house because she uses all of the same organisational methods that I do. Now, keep in mind that I lived far away from her for the majority of my life, so she did not teach me to organise. That organisation style was also not passed on to any of the other descendants that I spent a lot of time around growing up.
That my friend is nature.
Nurture, however, very likely plays a factor in many cases, but it’s usually difficult to judge to what extent. Whoever you associate with throughout your life has an influence on you whether you know it or not, and that’s something we can’t easily gauge.
The more functions in common you have with a person (particularly if you share the same upper functions), the more likely they are to influence your behaviours and attitudes. For instance, upper Fe users have very little influence on me because #1 I don’t use Fe unless I’m locked into my shadow functions #2 My feeling function is a lower function. Contrarily, upper Ni users are like fuel to me.
Because people who are related often have a few functions in common, it’s very likely that the influences they have on one another are going to be strong ones.
Thoughts, leute?
The Book Addict's Guide to MBTI: 
It’s my personal opinion that your cognitive functions and the order they follow comes from nature, but the way you apply your cognitive functions to daily life is a result of nurture. This is why some people with the same personality type can appear to lead completely different lives and have different values.
My family demonstrates some heredity in cognitive functions. My dad is an INTP and my mom is an ISFP. As an INFP I got my mom’s FiTe and my dad’s NeSi, while my sister, an ESTP, has my mom’s SeNi and my dad’s TiFe. So not only are my parents polar opposites in their functions, but because their functions are divided evenly between my sister and me, she and I are polar opposites as well. Incidentally, my brother, the only other sibling, is an INTJ, having all the same functions as my mom but in a different order.
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I wonder whether genetic inheritance divides by whether a specific function is introverted or extroverted. My parents are an ISFJ and an ENFP–both with Ne and Si in their function stacks–while I’m an INTJ with one definite ENFJ sister, an ESTP brother, a probable INTJ brother (with Asperger’s syndrome, however, which makes him show Si-ish qualities at times, most of them negative), and a probable ENFJ brother. So most of us are Ni-users, and the other is an Se-user.
If Ni- and Ne- genetics are folded, Five Factor-style, into “openness to experience,” our types might be easier to explain.
As for my parents’ families…both my ISFJ mom’s parents are Si-users–her dad is an ISFJ, and her mom an ESTJ. Her sisters are an ESTJ and an ESFJ.
My ENFP dad’s parents are both probably ISTJs–and both have poorly-developed Te. They never really accepted him, but they did get him to depend overmuch on his Si function (and, thus, he has never developed his tertiary Te). I think his sister is an STJ, but I haven’t been around her enough to know for sure. Naturally, his parents like her much better.
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I believe that the extent of our communications with our parents and personal experiences out of home, and the way we chose to or were taught to deal with them collectively influence our types.
I have an ESTJ mother and ENFJ father. My siblings are ISFJ, ESFJ. My youngest sibling is too young to determine his type. I am an INTJ.
My father’s side has a strain of mostly FJs, while that of my mother’s side has either SJs or TJs or both (xSTJs). Save for my INTP uncle, who was always considered the oddball.
But despite the functions and whatever they may be, what I did notice was that despite the functions, it was ultimately their upbringing that manifested the way they used their functions.
My mother, is the kind who cries a lot and was open about what she thinks/felt, that was something I picked up from from her. Despite the fact that I considered crying to be shameful, and something bad, I cried even. I even considered feelings to be the root cause of 99% broils that ever occured. I was the kind that thought “anything but feelings” yet I still cried. Of course now I’m older and understand better in the light of the subject of feelings. Even though, I still cry a lot when upset by anything, even if I dislike it.
My mother was always impatient to take a decision and enforce it (Te), while my father liked to take his time in decisions (Ni-Ti). While I do have a tendency to contemplate over what decision I should take it, once I take it, I’m quick to enforce it.
Bottomline is, when share a function with our parents, we learn to use it from them. Althought I have noticed people using Fe like Te.
People are complex, I have things to do, and a small box isn’t enough to fully flesh out what I mean to say.
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I got NO upper functions from my parents. I’m an ENTJ, my mom’s an INFP, and my dad’s an ISTP. However…for a long time (mostly when I was a kid), my mom was in the grip of her lower functions. While I was growing up, she was an even bigger control freak than I was! You could say I got my Te from her. However, I kind of have to keep both my parents at arm’s length to get along with them; the closer we get, the more we clash.
My sister, on the other hand, is an INTP (so she obviously got one upper function from each parent). She (usually) gets along well with my dad, but less so with my mom.
However, I’m far from the only one in my family who didn’t get any upper functions from his own parents. My mom’s parents are ESTP and ESFJ (grandfather and grandmother respectively), so my mom and her ENFP sister fit the bill in that regard. My mom’s other sister, who’s an ESTJ, is married to an ENTJ man (you can tell who I get along best with in my family), and their two sons are ENFP and ESFP. Meanwhile, on the other side of my family, my dad had an ENFJ father and ESTJ mother; he’s an ISTP, his sister is an ISTP, and his brother is an INTP. So…there’s kind of a hodgepodge of functions in my family. (However, when my dad’s siblings got married and had families, their offspring were a little more consistent with themselves, function-wise.)
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Wow, interesting mix of people
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Although I am Si dominant, I have been told by psychologists that I am very intuitive. I am pretty sure my dad is an INTJ. Is it possible that a dominant Si individual could be likely to exhibit more intuitive traits and behaviors if one parent has Ni or Ne as a dominant function?
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Yes, it’s very likely that your relationship with your dad has allowed you to develop your Ne function more than you otherwise would have.
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Is “gage” the British spelling, or was that a typo?
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That one would be a typo, thanks for catching it
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I’m a triplet, and actually have an INTJ sister; it’s certainly a very interesting experience, since my other sister is definitely an ESTJ. My INTJ sister understands has no trouble comprehending my oft-exaggerated sarcasm, while the ESTJ sibling takes every one of my jokes literally. The dichotomy can be fascinating at times, especially since all three of us are the same age. My parents are definitely upper Si users, but I’ve always had trouble typing them (I think my mom is an ESFJ, but my dad could be any sort is either an ISTJ or an ESTJ). The commonality of Te makes all of us task-oriented, but I’ve found that dealing with Si users can be difficult. I certainly have a much easier time communicating my ideas with my two best friends at college, an INFJ and an ENFP. I fairly certain that Ni runs somewhere on my Dad’s side, as it’s become apparent that at least one of my uncles possesses it. The differences between my INTJ sis and myself also demonstrate the power of environment-based functional development; my sister has always been more socially adept than me, and has fully developed her Te and is quite comfortable with Se as well. I spent more time in my head as a child, and thus have better-developed Ni and Fi. However, I can be prone to getting stuck in the dreaded Ni-Fi loop (it really is awful) if I neglect Te and Se too much.
Also, a question for Arvid: how do you feel about the John Locke’s famous “tabula rasa” theory of development? Is it too simplistic for you? Does still possess relevance in modern psychology?
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I applaud many of John Locke’s philosophies, but yes, I’d have to say the “tabula rasa” is a bit too simple when applied only by itself. To a certain extent I do believe that many of our ideas are influenced by the society we grow up in and the languages we speak, however, I also believe that some few of our ideas are inherent.
I don’t know whether it would be fair for me to judge whether it still has relevance in modern psychology –that would depend largely on which philosophers and psychologists you talked to.
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Similarly to what you said in one of your last paragraphs, it seems to me that nurture depends on what functions you already do or don’t have in common, and even then it could turn out many different ways.
For example, on one hand, I know an Fe-user who overcompensates with her Fe because she was raised by Te-user parents. On the other hand, I’m an upper Fe user, but I’m not particularly compliment-happy because neither of my Te-user parents are big on praise. I certainly don’t have a less developed Fe just because my parents didn’t nurture me using it, but growing up around them has made it manifest a little differently.
One of my INTJ friends (whom I statistically have far too many of — though I rather appreciate that), who is not so maturely developed, has a pretty overpowering, oftentimes offensive (for an INTJ, anyway. Kidding, kidding… or am I?) Te function that has been intensified over the years by his mother, who is an ESTJ.
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From my observations siblings share thinking and feeling functions more usually than sensing and intuition (though not necessairly the function’s order). Fictional example – if they matter anyhow – could be the Pevensies, and real-life example is my INFJ friend’s family, with ISFJ older sister and INTP younger brother. (BTW rised mainly by an ENTJ father…). You and your siblings are all Fi and Te users, if I recall correctly?
My favourite example of weird-type-list family is my INFP tutor’s. Her husband is an ENTJ, and their children are (age-respectively): ENTJ, ISTJ, ISTP and ISFJ and ISFP twins. My dear, what happened there? They have huge comunication issues as a family, too, maybe symtomatically.
However, this is all obviously anecdotal evidence. I’m an INFP only child rised by two Ni and Fe users, so, there.
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This is of course conjecture, but what do you think about the hypothesis that the cognitive functions are nature and the order of where they fall in the stack is nurture?
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I would certainly be open to the possibility, however I haven’t done much research on that particular question.
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Interesting. I’ve always wondered why my dad and younger sister really get along wonderfully, until I realized they are both ISTP. The way they play off each others humour is quite amusing. I think it’s slightly odd that out of nine immediate family members I am the only “N” ( INTJ) The rest of my family are “S”. Sometimes I wonder how I could possibly be so different from the rest of my family!
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I was just thinking about this yesterday! And trying to talk about it with my family…no luck there hahaha
tbh i was super excited to see the words “nature” and “nurture” together in my inbox — i love psychology. o,u,o
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Glad to hear it
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Interesting. In my own case, I’m the only INFJ I know of in my family; but since my parents are INTJ and ISFJ, I think I inherited a “mixture” of functions from them–my mom’s Ni/Se plus my dad’s Fe/Ti.
The other children in the family (I have seven siblings) also seem to have inherited various combinations of my mom’s and dad’s cognitive functions. One interesting pattern I’ve noticed is that all four girls (me and my three sisters) all appear to be xNxJs–just like my mother. I don’t think that’s a “nurture” thing, though–I mean, how do you “teach” somebody to be an upper-Ni user? I don’t think you can. I think it’s just something we inherited.
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This is very interesting, and I thank you for explaining it in a clear way that makes sense. About your last point, concerning the functions, I’ve noticed something interesting in my family. I’m an INFP (so dom-Fi), and my mom is an INFJ and one of my closest friends is an ISFJ. Over the years I’ve discovered I pick up Fe traits from them; the most prevalent example is that when I’m with other Fi friends, I feel the pressure to talk and keep the conversation going and make sure they’re comfortable, since that what the INFJ and ISFJ do with me––they don’t like it when it lapses into silence, though I do. So, while they haven’t altered my functions or anything of the sort, I think they’ve given me a different mindset, at least when with other people. I don’t know, I just thought that was something interesting to add. Thank you for your great post!
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I’m glad you did this post, I’ve been interested in this topic for a while now. And for the most part I’ve found like what you said, children sharing similar functions with their parents or grandparents.
I also find it interesting that your family and mine are similar in their types. I’m an INTJ and one of my siblings is an ENFP and the other is an ISTJ. Our parents are different, though, my mom is an INTJ and my dad is an ESTP.
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