That's why some college faculty are leading the charge to move the teaching of thinking skills out of isolated courses and into all classes. Much as writing is now often taught as part of every discipline, they argue, learning to think ought to be the goal of every class.
In the case of Mr. Withers's biology class, that's exactly what his professor, Sarah Wyatt, was aiming at.
Inspired by an initiative at Ohio University in Athens - where she was teaching - to focus harder on teaching students critical thinking skills, she directed her class to turn away temporarily from the usual round of textbooks, lectures, notes, and tests.
She asked them instead to break into teams and work to develop original hypotheses of a plant's development.
As Withers and his group began designing an experiment to test their hypothesis, they were forced to reconsider methods and conclusions.
What flaws and limits might be embedded in their approach? What could they know with certainty? What could they not know?
It was a challenging mental exercise, and as a result, Withers found he began thinking about biology outside class with more clarity, precision, and reflection than ever before.
At the University of Massachusetts in Boston, Esther Kingston-Mann is interested in training her students to think like historians rather than biologists.
But her goal of encouraging her students to do their own thinking is similar to that of Professor Wyatt's.
Like Wyatt, she has her students occasionally close their textbooks. In her course on the cold war, she asks them to read newspaper accounts instead.
They scan articles dating from the "red scare" in the 1920s on through World War II and then read further new accounts of relations between the US and the Soviet Union in later decades.
Later they collaborate in small groups, trying to identify in the newspaper clippings the voices being used to tell the story at a particular moment - and to note which perspectives and voices are missing.