Living With a Whole in Your Head or Functioning Without One

That first part is misleading, in that mind and body together constitute the irreducible whole of the human person, and that's just the way it is. Once you separate them -- as does, for example, Descartes -- there's no forcing them back together. It reminds me of a wise crack by Thomas I read yesterday, that

strictly speaking, it is not the senses that perceive, but man perceives through them.

We can of course distinguish between sense and intellect, but never separate them without separating man from himself, i.e., dividing his holistic personhood.

You could say we are a "part" of the Cosmos, but then again, man as such is uniquely intertwined with the totality of being in such a way that it is given to us in the evolving space we inhabit between intellect and intelligibility. 

It is these two -- intellect and intelligibility -- that uniquely mirror one another in man, such that to separate them is to deny what man is, precisely. And again, once separated they can never be reunited in an organic way. 

The Catholic philosopher Maurice Blondel said that "there are no more difficult problems to solve than those that do not exist" (Tyson), the so-called "mind-body" problem being a quintessential example. Why separate what God -- or whatever -- has joined together in wholly patrimony? 

To the extent that man is a "part," it is only in the context of a deeper complementarity between part and whole, both horizontally and vertically. 

Analogously, our individual organs are in one sense "wholes," but parts of an organism that displays a deeper kind of wholeness. Likewise, the individual person is a whole, but always a part of a deeper and more comprehensive wholeness. 

What and where is this latter wholeness? It cannot be found "below," in the (merely) material cosmos, even though it too reveals an irreducible wholeness as described by modern physics. Whitehead, for example,  writes of how

We habitually speak of stones, and planets, and animals, as though each individual thing could exist, even for a passing moment, in separation from an environment which is in truth a necessary factor in its own nature.

Now, what is the human environment? That's a tricksy one, because other animals are adapted to, and enclosed in, specific circumstances which they can by no means transcend; rather, the world is as big -- or as small -- as their perceptions of it. 

My dog surely exists in the Cosmos, but she doesn't know that. The biggest her world gets is when she goes for a walk and is exposed to novelty.

Novelty. That was a big one for Whitehead, an irreducible category of being. He suggested that life itself is  "an offensive directed against the repetitious mechanism of the Universe." As I wrote in an old post,

everything participates in everything else in ways that are far beyond the ken of 19th century atomistic science. Furthermore, in a post-relativistic cosmos, both space and time are nonlocal, so things are also temporally connected in ways that materialistic science cannot disclose.

Back to man's proper environment. Turns out that 

man's world is not merely and neatly the rather abstract "totality" of all there is, but an intermingling of specific "surroundings" and universal "world" (Pieper). 

There is a kind of endless dialectic between the two, in that we live in our immediate surroundings, and yet, have a "universal openness" that frees us "from the specifics of a habitat." Man is 

"a being surpassing himself and the world," really not bound anymore to profess, "I am part of the world. I am embedded in the world." 

No, we always surpass ourselves and our environment:

it insults the dignity of man's spirit to lead a life so much confined and imprisoned within narrow considerations of immediate usefulness that his own small environment utterly ceases to be a window on the larger "world." 

To be thus totally absorbed in a mere fragment of reality, to "function" rather than live, is not human; yet to be so tempted is indeed all too human (Pieper).

Tempting, but I'll pass.