Intellectual property is a term that bears some resemblance to real property but the two are very different. IP represents the product of knowledge workers time and resources. Real property represents physical objects. Sometimes a knowledge worker produces an idea that makes its way into the physical world. But that is another discussion.
Walk down the street and count the number of Craftsman style homes you see. Nobody holds the patent on the architectural design.
The Craftsman style home represents mixed-use live/work space and creative expression. It’s like asking a builder to design the ideal home for his family to live, work, learn, and play in. Sharing architectural elements that are visibly similar led to cultivating a creative community around the common elements and the designs improved over time. Now they are very popular.
As builders copied design elements like low-pitched, gabled roof and a front porch with tapered columns the Craftsman style became functional and beautiful. Imagine if a regulating organization had barred builders from using these iconic design elements with copyright infringement lawsuits. Instead of inspiring builders to improve on existing techniques, the style would have been stifled and maybe died off completely.
One of the problems with intellectual property law is creating scarcity where there is not scarcity. Jeffrey Tucker has an interesting comment on this idea and I’d like to relate it back to real property and architectural design.
An architect who copies the plan of a home from another architect is not stealing property, only ideas. The home still needs to be built with real materials and because it’s physically separate from the original nobody would call it a copy in the same sense that people copy software, or music, or digital art of any kind. A reproduction, sure, but not an exact copy. The architect who builds his career on duplicating others’ work down to the last detail won’t get famous but will make a living because people want beautiful, functional things that look like other beautiful, functional things.
If it’s a good idea, it should be reproduced as often as there is demand for it.
Aaron Bronow 
I agree that it is difficult to always know when one has subconsciously absorbed another person’s idea…storing in the brain for later retrieval. But, I would submit that the “architect who copies the plan of a home from another…” would not be creative, and therefore, may be an infringement. But, when building, if one is inspired by ideas seen in another’s design, that is a different story. When IP makes it’s way into the real world, as you say, it’s creative and inspiring. But to “sit on it” so to speak, and not share it, I think would stifle further ideas. Someone once told me the best compliment to an artist is to be copied. Do you agree?
I agree that copying is a compliment. When you say an architect who copies is not creative I think there’s a difference between an exact copy (as in digital copy) and a copy of a building plan which is not exact, but designed to look similar.
OK, I’ll give you that…