Lavish architectural etchings cover the walls from floor to ceiling of the Toronto apartment of Robert Jan van Pelt, perhaps an expected flourish for the home of a professor at a school of architecture.
Closer inspection reveals that, rather than the gothic beauty of the Chartres Cathedral or the Art Deco heights of New York's Chrysler Building, his etches are Giovanni Piranesi's dark depictions of imaginary prisons.
The display of oppressive penitentiaries as architectural marvels mirrors Prof. van Pelt's proposition that the crematoria at Auschwitz, the Nazi death camp that has become a symbol of the Holocaust, is one of the greatest buildings ever constructed.
That notion, paired with his seemingly contradictory suggestion that the site of the camp should be abandoned to nature, has placed him at the centre of an awkward debate in Europe over what to do with the crumbling site of mass death that is now a destination for mass tourism.
In conversation, Prof. van Pelt carefully explains his ideas like he is constructing a building, laying a foundation and then placing propositions one atop another.
The crematoria, where an estimated 1.1 million people, mostly European Jews, were gassed and incinerated, are some of the few structures that truly matter in the course of human history, he says. That separates it from sites that architects traditionally consider humanity's most important constructions.
"It really wouldn't have made much of a difference if St. Peter's Basilica would have been built or not. It would be a real pity if it was destroyed now but humanity would have done very well without the Cathedral of Chartres or, for that matter, the Pantheon in Rome," he says.
"But I think that something really changed with the crematoria at Auschwitz because there we have a building located right at the core of the great question of what it means to be human and what are the prospects of the species. The Holocaust is the kind of event that shows us that the species has the ability to destroy itself.
"I would say that in the case of the crematoria, [the building] does matter a lot. Without the crematoria, the Holocaust would not have become the crime it became."
His idea is a triumph of meaning over majesty in a field that has deeply valued aesthetics.
"I don't really care about buildings," he says. "But I care about the way buildings are represented and remembered, the way they function in a wider culture."
It is an idea that has caused him strife with some colleagues, particularly at a U.S. university before his move to Ontario's University of Waterloo in 1987.
With his thinning, grey hair and fondness for comfortable sweaters, he looks every inch the "university professor" that his business card advertises.
A note to himself taped to the inside of his apartment door - a checklist of things to take with him: power cord, cell phone, appointment book - could reinforce the stereotype of the absent-minded professor but likely reflects the distance of his home from his office (100 kilometres almost exactly).
Prof. van Pelt, however, is not an academic who wallowed in the abstract, controversial delight of his idea.
Once convinced that Auschwitz was the key to understanding the importance of architecture - an epiphany he had while defending his PhD thesis in 1984 in his native Holland - he embarked on a thorough and detailed study of the Auschwitz camps.
He spent months in Poland studying architectural drawings, planning documents and other archival material for the camp and the town of Oświęcim, which was rebranded "Auschwitz" after the German occupation.
"Tourists used to go to Auschwitz in the 1900s to have a good time there," he says, showing a cheerful postcard from the era. "The adjacency of utopia and dystopia became the engine that began to drive my research."
In 1997, Prof. van Pelt presented the "Strategy For the Reconstruction of the State Museum Auschwitz-Birkenau" to Poland's president, a plan designed to ensure the preservation of the camps.
Prof. van Pelt's work has led to several books on the subject as well as involvement in films, including Mr. Death by American Academy Award winning director Errol Morris.
Prof. van Pelt's position as a world authority on Auschwitz has recently brought close scrutiny to his part in a discussion on what to do with the crumbling site of the death camps, more than 60 years after the close of the Second World War and 10 years after his proposal to preserve them.
As a potent symbol of the Holocaust, close to a million people each year visit what German magazine Der Spiegel described as "the world's most horrid place." Prof. van Pelt goes there once a year with a tour of Holocaust scholars and teachers. He met his wife on one such tour.
As a tourist destination, however, Auschwitz presents many conundrums.
Parts of the sprawling site (there are three camps) have been retained and reconstructed and are in good repair. They include the main gates with the haunting slogan "Arbeit macht frei" (work shall set you free). Other portions, primarily in the Birkenau portion of the camps, where most of the Jews were killed, are crumbling ruins, where some 400 brick chimneys are all that remains of wooden buildings.
"The fact is that the remains of Auschwitz are shells and shadows of the periphery of what is the core of the event, which is the industrialized killing of people.
"In the master plan for mass tourism, which Auschwitz is, we are basically talking about things like the location of the toilets. This was a big issue... Given the size and the distances of places, the only place where the toilet building could go - and where it, in the end, went - was right close to the crematoria. That is the reality of mass tourism."
But normal tourism economics do not apply.
"In order for this museum to run, it would need to charge at least $10-15 a person to go into Auschwitz. We accept that when we want to get into the [Royal Ontario Museum] but it is a very difficult thing to sell at Auschwitz. Think about when the first survivor who comes there: ‘You want to charge me to go to the place where my parents were killed?'
"All the normal ways of earning money don't apply. If a museum needs money it comes from the gift shop; at Auschwitz, the museum gift shop is a problematic thing.
"You might say everyone needs to eat, let's get it out in food. But I tell you not everyone wants to eat so much at Auschwitz. It's not like you can have a high-end restaurant making profits there. How are tours going to organize lunch? You cannot really do a picnic in Birkenau. It is a problem."
Given the lack of resources and the inevitable decay, Prof. van Pelt said one solution quickly emerges. What he says next is stripped of sentimentality but not of respect.
"Most people talk about the future of Auschwitz very emotionally without actually having any knowledge about it and without actually having any grasp of the incredibly contradictory nature of the site in terms of preservation and management.
"I say they should maybe allow Birkenau to be surrendered to nature - which does not mean putting condos on it but simply seal off the site and we allow nature to take over in a kind of symbolic gesture that humanity failed so terribly there that we now give it over to the cockroaches and grass and whatever. They haven't screwed up as badly as we have."
He adds an important caveat: It should not be done as long as there are survivors who may wish a return visit to the site. (He, himself, had a Jewish uncle who died in Auschwitz; he was named after him.)
"People will have to make choices... let us at least make a distinction between what is critical for us, what is important for us and what is merely significant.
"In Auschwitz they were restoring the sewer works of the camps not because it was the most important but because it was the only thing that was not contested.
"Because whatever you do in Auschwitz someone will say that you made the wrong choice."