I don't think I can agree with any of that.
On grades:
Plenty of INTPs prioritise grades. Grades are a (flawed) measure of intelligence, which INTPs value. I see no reason that INTPs alone would be immune to having their ego fed.
On excessive intelligence:
Read any thread on this forum about IQ. It's the INTP version of dick length. Actually, probably the NT version of dick length, but INTPs are certainly not exempt. I'm not sure why you think INTPs don't value high intelligence.
On forming sentences:
I don't see any reason to correlate the inability to communicate using cohesive sentences with the INTP type. Actually, I'd posit that it's probably rather offensive to a well-developed INTP.
On perceived importance and dependence:
Seems to be directed at someone who you perceive has wronged you. I won't bother to elaborate.
On cleanliness:
Not all INTPs favour filth. I'd say that those that don't at least aspire to a standard of cleanliness and order are in the minority. Further, it's also not a trait that ought to be worn as a badge of honour...
On math:
What exactly excludes 15 other types from a propensity for mathematical concepts?
On acting upon ideas:
Once again, this sounds to me like a personal gripe. INTPs are just as capable as everyone else of having only few good ideas upon which to act. INTPs aren't exactly the pinnacle of inspiration.
On staying in the moment/being present:
What makes consistently being 'in the moment' unreachable for INTPs? I may be wrong here, but I'm of the belief that this ability is a product of wisdom and certainly not one of type.
Something I just realised: To me, that post echoed an attitude of self-defeat. You gotta get some positivity in your life. Perhaps you will benefit from this forum and gain some perspective and wisdom.
Welcome to the forum
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I hope you stick around
So much of what you have counter argued here only solidifies many ( not all ) of kanani's bullet points.
On grades:
My friend and i ( both intp ) never gave much thought to grades, we where busy dreaming up new things to make in the tech lab. Grades are a vanity tool more often than not, and to get good ones you have to jump through sub par hoops just to prove your willingness to do so more than prove your mental ability to do so. I was that kid who never did homework, never came to class ( but was still at school ) unless there was a test, and ( nearly ) never got less than a B on those tests. My friend dropped out and became a CAD architect.
On excessive intelligence:
You misunderstood kanani's point by a mile and a half. He means If you think that being smart somehow makes you more functionally useful. But nearly all intps will tell you, its just as much a curse than it is a boon. Thinking takes energy, a lot of it.
Its like your thoughts are a diver in an endless sea, where your iq is how fast you can swim. Out in the water you come across many truths and mistruths that you have to ether hold on to or untangle yourself from, all the while fighting off sea monsters of unhealthy and damaging thought. Its exhausting to venture as far from the shore as we do.
On forming sentences:
Intp's seem to have a good grasp of how language should be structured. Not because it is logical or anything, just that it sounds better in our heads.
An intp is almost always staging internal debates, advocating the different sides of an argument within our heads until we are sure we wont make a fool out of ourselves by voicing a subjectively true, objectively false statement. So when a sentence does not flow in our heads or articulate our meaning we rework and restructure the text until it does. We dont always have the time to think out our words while speaking, however, so speaking an idea can be cumbersome and even stuttered.
On perceived importance and dependence:
Of those I've spoken to, common theme of most intps is that they know that they don't know. And it is infuriating to see some brazen fool speak as if they know everything while spouting half baked thoughts. But unlike entps, we don't oft feel compelled to enter in debate over the correctness of that person, nor do we slowly go crazy when we haven't debated self rightness with another human being for a few days.
On cleanliness:
I admit, im not one for daily showers or spending longer than 30 seconds viewing myself in the mirror as i wash my hands. It just goes back to that vanity thing, it feels pointless and shallow to spend so much time appealing to other human beings senses when you don't really care for the brain that interprets them.
On math:
This i agree with you on this. While math has always been my thing, i dont see why any other type cant do it as efficiently as any intp.
But a counter argument is that the Intp group has the highest Gifted Intellect ratio of any of the mbti typology.
On ideas:
If only i could subject you in the torrent of ideas that blow through my mind every day. Finishing a project means to constantly bat away better ideas and settle with just finishing something in a reasonable time-frame. Take too long trying to make it perfect, and your mind gets bored of the concept and wanders away, trying to apply everything you just learned to something bigger, more useful, more automatic, more complex and more perfect.
On staying in the moment:
Many intps i know (and myself) are the definition of walking ADD( see above) , this persists.
Welcome to the forums kanani, hope my dissection of these points ring accurate.
( I dont mean to sound so mater-of-fact, its just a lot simpler to put an idea in repose when stated as such )