George Lakoff argues in "
Where Mathematics Comes From" that mathematics results from human cognition, and can only be understood through an understanding of human cognition.
He analyses mathematical ideas based on human experience and human cognitive processes such as metaphor.
For example, he says that four basic metaphors structure our understanding of arithmetic: collecting things, building things, using a measuring stick, and moving along a path.
So, to answer the main question in this thread (how does math relate to the physical world), I believe he would say that math relates to the physical world via human per/conception/reasoning.
Note that he does not deny the inherent ability of humans to perform mathematical tasks - he goes into detail about recent research e.g. on infants that shows that they look longer when one object is placed behind a screen, and then one more, but when the screen is removed, three objects are sitting there. Tiny infants (just weeks old) somehow know that this is impossible. This line of research suggests that we come into this world pre-programmed to count, add, and subtract numbers/objects from 0 to 4 or 5.
Lakoff argues that more complex mathematics is ultimately founded on this simple math, and is accomplished via cognitive processes such as metaphor.
He rejects the Platonistic idea of mathematics, saying that all mathematics that we can ever know comes from human cognition. Instead of seeing mathematics as transcendent, he says that it is the result of human culture and intelligence.
The connection between mathematics and the physical world is not what it seems.
The connection between mathematics and
our experience of the physical world is mediated through our minds.
I have actually not read the book (after all this!

), but heard him (and his coauthor, Nunez) talk about it once.
What he said seemed to make sense to me, but I do not have the background to really judge.
Let me guess - mathematically uneducated buffoons who have ingested one too many hallucinogenic fungi in their time, right? They're the ones with the insight, and everyone else falls under your sweeping indictment as the 'walking dead?' What a crock.
I think people above were trying to say that you might have expressed your message in a more kind or gentle way, PA. This quote seems quite confrontational and angry, and it was from the beginning of your back-and-forth.