Van Fleteren answers in Latin: " Fabricando fit faber."
Which means, he said, "You sit your behind down in the seat and do it."
Or more precisely, "Working makes the worker."
The project: Translating, annotating, indexing, and commenting on a 1,300-page biography of St. Augustine of Hippo, the theologian, philosopher, and writer whose major works established an underpinning of Western Christianity.
"He is," Van Fleteren said in deliberate understatement, "a very interesting character."
Augustine spent most of his life in northern Africa, a wildly enthusiastic sinner who later repented, becoming a priest, bishop, and saint. He spoke and taught about salvation and divine grace, helped conceive the ideas of original sin and just war.
He died in 430 and was declared a saint soon afterward. Van Fleteren believes him to be the most important figure in Western thought, even more than Plato or Aristotle.
In 1695, Louis Sebastian Le Nain de Tillemont, a French priest and historian, wrote what is considered the most comprehensive biography of Augustine. In his 16-volume history of the church, covering the period from after the apostles until the year 513, he devoted an entire volume to Augustine.
For Van Fleteren, even finding Tillemont's full, unabridged biography was hard. He knew it was out there somewhere, having heard of a 1732 edition published in Venice. A search in this country failed to locate a copy. Eventually, he found an edition in Austria, in the library of the University of Salzburg.
That's what Van Fleteren translated, sending the third and final volume to the publisher on Friday. He planned to celebrate - a day behind the Feast of Saint Augustine, patron saint of brewers - with a glass of wine.
The professor became interested in Augustine when he was 25. Now he's 73. And still fascinated.
"He's completely immersed. He's addicted to it the way a 16-year old is addicted to video games," said Marc Moreau, chairman of the La Salle philosophy department.
Once, upon returning to work on a Monday after a gorgeous, sunny weekend, Moreau said, he asked Van Fleteren how he had spent his time off. The answer: outside in the sun - reading Augustine in Latin.
The translation was no academic exercise, Moreau said. The first two volumes already have been recognized by scholars, who credit Van Fleteren's nuanced understanding as opening new approaches for English-language studies of Augustine.
In March, the university recognized Van Fleteren with the faculty distinguished scholarship award. Provost Joseph Marbach described Van Fleteren's scholarship as outstanding "in its steadily productive pace, in its high quality, and in the recognition it has received from an august body of peers on both sides of the Atlantic."
It almost didn't happen.
Van Fleteren began the project as part of a four-person team of scholars. He finished as a team of one. Death, illness, and personal trials vanquished the others.
It could be lonely. At times, he considered giving up.
Augustine was an insomniac, writing by candlelight, and during his years of work, Van Fleteren become a bit of one, too.
Of course, Van Fleteren said, he didn't devote every minute of 25 years to the project. He also wrote articles and book reviews, and co-edited the critically acclaimed Augustine Through the Ages: An Encyclopedia, published in 1999.
He traveled, for research and pleasure, becoming perhaps the only American to visit St. Andrews and not play a round of golf. He became an expert at bridge. Fell in love with a woman. And lost her.
Always, the translation was there.
"I came to the realization I'm probably the only fellow in the world who could finish this book," he said. "This is not an act of genius, it's an act of perseverance. Augustine would say it began, continued, and finished with an impetus of God."
He wore out three laptops, used up paper and pens. There might have been an easier way, he said, but computer-translator systems weren't widespread when he started in the late 1980s.
Moreover, the task of translation was no sterile procedure. Meanings as well as words had to be deciphered, interpretations leveled. He turned hagiography into true biography.
Publication of the last volume is scheduled for next year, though that won't end Van Fleteren's work on Augustine. He's already writing new articles and papers.
"Every age is the age of Augustine," Van Fleteren said. "But it's a different Augustine."