The thing about N is that it's pattern finding, not necessarily about the bigger picture. The perceiving type is required to hold the bigger picture because it requires one to suspend conclusion until the real conclusion is actually found and not merely evaluated and determined.
The J type will probably ponder until "It's good enough for me" where as the P type will ponder until "Is the picture complete"
Another thought about it is that Js generally take on a lot of assumptions without realizing it. Like in math, 1+1=2. Everyone is fine with that and nobody bas a problem. But is going to be a P that's going to question the underlying assumptions: does ! + 1 really equal 2? And yes, there's a 1000 page mathematical proof in 2 volumes proving that 1+1 indeed equals 2.
The trigger that showed me that Watts is a P and not J is the style of his thinking. He's questioned just about everything and thus gained a much deeper understanding of the things he talks about. Citing clear examples and thought experiments initiated by the word "suppose that" or "imagine that".
Stereotypically, Watts as an INFJ would have assumed a great many things and would be engaged in an emotional level with the audience and not the analytical level. The topic would also me more of mysticism talking about the chakras and the pillars of wisdom than actually going through the mechanics of spirituality and clear delineations of ideas.
If you can see it, his speech is that of math.
Let x equal the universe.
x+y = parallel universe
which is similar to
suppose we have two circles.
then suppose we draw another circle.
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more on J/P
There is some research linking the J type to a left brain dominance and the P type to a right brain dominance. The left brain being the ego, self and boundaries where as the P is about the whole picture, relational thinking and holistic thinking.