I'm perfectly willing to concede INTP - it's pretty likely. But when you sit down and read "The World as I See It" which is much closer to a personal expository of "the real Einstein" than his work on physics, I end with questioning whether or not he was a mathematical INFP. I'm INFP, very INFP, I've tested this way for a decade. However, I also have aced every math and physics course I've ever taken through Differential Equations, Multivariable Calc, Linear Algebra, etc. I haven't taken VERY advanced physics courses, but the idea that INFPs cannot have logical aptitude is simply inaccurate. So when I stumble across Einstein's writings of a personal nature, I find him more affected with an aversion to conflict, a strong sense of empathy, and an idealism that is even beyond my capacity - such as the belief that military could be abolished. This makes me sit back a little and question how much of an INTP he really was...
e.g. "I maintain that cosmic religious feeling is the strongest and noblest incitement to scientific research." - Albert Einstein
So, here are some more quotes from "The World as I See It" by Einstein that put him more in the idealist camp than INTP:
"The ideals which have lighted me on my way and time after time given me new courage to face life cheerfully, have been Truth, Goodness, and Beauty. Without the sense of fellowship with men of like mind, of preoccupation with the objective, the eternally unattainable in the field of art and scientific research, life would have seemed to me empty. The ordinary objects of human endeavour—property, outward success, luxury— have always seemed to me contemptible."
"This topic brings me to that worst outcrop of the herd nature, the military system, which I abhor. That a man can take pleasure in marching in formation to the strains of a band is enough to make me despise him. He has only been given his big brain by mistake; a backbone was all he needed. This plague-spot of civilization ought to be abolished with all possible speed."
"The fairest thing we can experience is the mysterious."
"Enough for me the mystery of the eternity of life, and the inkling of the marvellous structure of reality, together with the single-hearted endeavour to comprehend a portion, be it never so tiny, of the reason that manifests itself in nature."
"To-day also there is an urge towards social progress, towards tolerance and freedom of thought, towards a larger political unity, which we to-day call Europe. But the students at our universities have ceased as completely as their teachers to enshrine the hopes and ideals of the nation. Anyone who looks at our times coolly and dispassionately must admit this."
"The true value of a human being is determined primarily by the measure and the sense in which he has attained to liberation from the self."
"The lack of outstanding figures is particularly striking in the domain of art. Painting and music have definitely degenerated and largely lost their popular appeal. In politics not only are leaders lacking, but the independence of spent and the sense of justice of the citizen have to a great extent declined. The democratic, parliamentarian regime, which is based on such independence, has in many places been shaken, dictatorships have sprung up and are tolerated, because men's sense of the dignity and the rights of the individual is no longer strong enough. In two weeks the sheep-like masses can be worked up by the newspapers into such a state of excited fury that the men are prepared to put on uniform and kill and be billed, for the sake of the worthless aims of a few interested parties."
"it is precisely among the heretics of every age that we find men who were filled with the highest kind of religious feeling and were in many cases regarded by their contemporaries as Atheists, sometimes also as saints. Looked at in this light, men like Democritus, Francis of Assisi, and Spinoza are closely akin to one another. How can cosmic religious feeling be communicated from one person to another, if it can give rise to no definite notion of a God and no theology? In my view, it is the most important function of art and science to awaken this feeling and keep it alive in those who are capable of it. Only those who realize the immense efforts and, above all, the devotion which pioneer work in theoretical science demands, can grasp the strength of the emotion out of which alone such work, remote as it is from the immediate realities of life, can issue. "
"But the pursuit of scientific truth, detached from the practical interests of everyday life, ought to be treated as sacred by every Government"
"Communities tend to be less guided than individuals by conscience and a sense of responsibility. What a fruitful source of suffering to mankind this fact is! It is the cause of wars and every kind of oppression, which fill the earth with pain, sighs, and bitterness."
"To see with one's own eyes, to feel and judge without succumbing to the suggestive power of the fashion of the day, to be able to express what one has seen and felt in a snappy sentence or even in a cunningly wrought word—is that not glorious? Is it not a proper subject for congratulation?"
I don't know, I may be looking at him in a biased way. He says some things I find very illogical and poorly thought out in his sociological and political views - as if he's got some deep emotional impulse pushing him to say what he wants to be true as opposed to what he knows is true.
I just don't see his personality as a quaternary Fe, he seems to have a major Fi in him... Or maybe I just see whatever precisely my own "Ne" is in his "Ne." I don't really believe the MBTI categories are as rigid as it would lead one to believe. But, they are a fun categorization tool.