The sarcastic tone is a sign of NP humour. It was playful rather than ignorant and I was quite enjoying it
. I'm guessing it is a common NP thing at least, maybe humour is type free.
If that is the case, that is fine and I admit its an error in my judgement. I should've taken it with more humour.
Logic, by definition is completely objective. Sometimes the term 'subjective logic' is mistakenly used to depict Introverted Thinking. What is meant by this is that Thinking in the case of Introverted Thinking is inspired internally or by subjective data. An example of this would be a mathematician inspired to analyze a problem by an abstract vision of the problem he has conceived in his mind. This is one reason the INTP type tends to be in close affinity with intellectual disciplines that require abstract reasoning first and foremost.
This approach to Thinking contrasts with that of Extroverted Thinking, in the latter case thinking is inspired strictly by an external agenda. A classical example of this is a businessman trying to solve a problem that directly involves his business, or a general trying to win the battle that his external circumstances are profoundly influenced by. For this reason Extroverted Thinking is best known for implementation of ideas rather than their conception, and vice versa holds true for the Introverted Thinker for reasons mentioned in the first paragraph.
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It is indeed the case that the Thinking types tend not to be talented at the use of their Feeling faculty and because of this often lack skills associated with a competent use of Feeling. It is also true, as you mention that this leads to a callous attitude. This obviously means that the Thinking type has difficulties of his own, but they are clearly less severe than that of the Feeling type. A person who lacks Thinking skills simply lacks structure in their worldview. Such a person will have only a very fuzzy idea of who they are and how they should live their life. This is the problem of flightiness that sakuraba mentioned in the OP. The negative consequences of callousness are obviously much less severe, as callousness leads to nothing nearly as deleterious as a situation where one lacks a sense of purpose in life as well as a clear sense of self.
Logic is the most objective concept that humans have approximated. Logic efficiently utilised in maths, is hardly falsified, that is correct, but the person utilising its logical variant in understanding human tendencies, is not as efficient in its usage, since human nature is not as accurately quantifiable as say maths. A person's subjective experiences in life, limit the use of logic because of constraint by time in history, culture, family, peers, nature to name some. Imperfections, in this regard have to be accepted, otherwise effective critique in logic can be hindered and contextual understanding of MBTI in the remit of other thought, which would hinder precision and refinement. Taking an absolutionist approach to the perfection of one's logical perception, will cause a slow down, in taking into account more subtle methodological critques of one's perspective. There is difference in acknowledgment and proactively critiquing one's absolutionist approach.
Your point is valid, when taking in various assumed variables about the internal and external world. It depends on what environment the Thinker or Feeler is trying to progress in, if there is heavy focus on a value system and social cohesion, there can be situations, where the thinker can potentailly suffer from his or her feeling deficiencies. Also this is under the assumption, that the "purpose" you describe is of an equal race end, between thinkers and feelers. Thinkers may have a solid purpose, while NFs, being of the idealist quandrant have a similarly hypothetical equivalent of "purpose", but are perfectionists, so want further refinement, this can cause a relative slowdown true, however the irrational function of NF, may cause them to work harder once that purpose is obtained, than the logics of a thinker would, causing societal progress i.e Martin Luther King, Gandhi, to mention the prominent ones or at least arbitary self gain, which is considered a bad thing for some. All humans are selfish though in some manner, it varies, overlaps and is a lot down to perception.
The clear sense of self issue, is a drawback, individual's emotions are hard to measure objectively, posing more difficulty in the one that has more prominent usage in it, that is fair. I have no objection that Ti/Te users would be at a natural advantage in impersonal analysis generally and the difference you explained between Ti conceptual advantage and Te implementation advantage.
Btw, I find your opinions very interesting and thought provoking, even if I don't agree with everything, there aren't many that contribute so much in their posts.
