The 12-week course will include different ways of evaluating an argument.

For 20 years at Dartmouth College, Walter Sinnott-Armstrong taught a class on how to reason and argue. He figures that over the two decades, he taught around 2,500 students. But beginning next month, Sinnott-Armstrong, now a professor of philosophy at Duke University, will teach that course to around 150,000.

The class — “Think Again: How to Reason and Argue” — is one of 10 MOOCs, or massive online open courses, that Duke is offering through a partnership with a California-based company.

More than 300,000 students worldwide have signed up for the Duke courses, which range from “Bioelectricity: A quantitative approach” to “Image and video processing: From Mars to Hollywood with a stop at the hospital.”

Sinnott-Armstrong’s course, which he is co-teaching with Ram Neta, a UNC Chapel Hill faculty member, is, so far, the most popular of the bunch.

“I never imagined I’d have so many students during my entire career,” Sinnott-Armstrong said. “It’s exciting, and I’m really looking forward to it.”

Duke jumped into the MOOC pool this summer, when it joined with 11 other major research institutions — including the University of Virginia and the California Institute of Technology — to offer classes through Coursera. The Silicon Valley for-profit start-up provides a single platform for all the schools to offer the free, no-credit courses.

Duke made the jump, said Provost Peter Lange, the university’s chief academic officer, because “we think this will extend our reach and our faculty’s reach globally, but also help bring innovation into our own courses and could substantially influence how we teach students here on campus.”

MOOCs have become the rage in academia, with a number of additional universities recently affiliating with Coursera and others offering online classes through other platforms. In August, Coursera announced total enrollments in all their classes had exceeded one million.

Sinnott-Armstrong said his course in particular has amassed so many enrollments because — unlike many other classes that require higher-level skills and more background — “this is a general course that teaches a skill that could be useful for anyone.”

Many people, he said, from all walks of life, want to learn how to think about issues that matter to them.

“Everyone recognizes the importance of reasoning and argument,” Sinnott-Armstrong said, “and what we’re trying to teach is how to evaluate an argument, whether it’s a presidential debate or when you buy a car or decide to take a trip. How do you know what’s a good argument?

“We’re going to give people the tools for that analysis, and that’s very valuable for everyday life.”

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