A very fine Italian house

PIOMBINO DESE, ITALY — One afternoon in the middle of September, I stepped off a train onto the rain-slicked streets of this sleepy, well-kept town 25 miles northwest of Venice. After dashing for three blocks through a howling, late-summer storm, I found myself face to face with the house that arguably has had a broader, more lasting influence on American residential architecture than any other single building: the Villa Cornaro, built beginning in 1553 and designed by Andrea Palladio, who was born in Padua exactly 500 years ago today.

Looking back in my direction from atop a broad sweep of stone steps was the piece of architecture that inspired Thomas Jefferson's first stab at a design for Monticello, helped give the White House its projecting North Portico, and has since inspired thousands of ambitious designs in subdivisions across America -- including, in recent years, enough McMansions to fill a good-sized suburb. This was the one Palladian villa I'd always planned but hadn't yet been able to visit; it was also, I hoped, one that might shed some useful light on the complexities of architectural influence, and maybe explain why the very idea of appropriation is more fraught in architecture than in any other art form.

If a sculptor, filmmaker or composer is talented enough to produce a group of acolytes, or creates a style that seems irresistibly easy to crib, it hardly matters if the resulting copies are clumsy. An unsuccessful stab at Jackson Pollock-style action painting never did anybody any harm. A terrible Hemingway-esque novel can be stashed benignly on the bottom shelf.

But bad copies of brilliant buildings never disappear, at least not without the help of a wrecking crew, and they can't very easily be camouflaged or tucked out of sight. And when you consider that the vast majority of structures that go up in our cities every year are not designed by professionals -- and are therefore invented completely by means of indirect influence, with contractors often relying on blueprints that are already copies of copies -- you begin to realize that the act of architectural borrowing, in the wrong hands, can be a pretty destructive force.

Few architects have been as widely, energetically or crudely copied as Palladio. His outsized legacy is partly thanks to the clear, graceful appeal of his designs for villas and churches, but has more to do with the fact that he produced the famous pattern book in architectural history, I Quattro Libri dell'Architettura, or the Four Books on Architecture. It explained in uncompromising but patient prose how to apply the details and proportions of classical architecture to new construction. It also included a much-studied illustration of the Villa Cornaro.