> I see no more philosophical justification for physical property than for intellectual property.
TL;DR: physical property="who gets to have this", 'intellectual property laws'="who gets to make money from this".
Physical property isn't natural, but it's an answer to physical scarcity, which is natural.
You and your friend can build identical houses, they can't be both exactly at the same location.
Physical property creates a non-volatile answer to the question "Who gets to build his house there?".
All working societies must address this problem (even societies in which money doesn't exist), hence "property" (which I don't claim is the only answer).
Texts, recordings, etc. are a completely different issue.
Original works might be rare, however, there's no scarcity in using them : you and your friend can both listen to your copy of a recording without interfering.
So there's need to answer "who gets to listen to this recording?", as there's no scarcity, and thus, no conflict.
The conflict lies between distributors, because the only scarcity that remains, when works can be copied for free, is in the exploitation.
For distributors, money is scarce, so question becomes: "who gets to make money from this recording?".
This is a very different question, which already presupposes the existence of money, and exploitation.