Vol. 74 No. 4 April 1997 • Journal of Chemical Education 365

Chemical Education Today

conditional logic. It appears that reasoning can be taught,but we are not doing it! (Of course the data might also im-ply that our students’ abilities are already at such a highlevel that they cannot be improved, and we could argue thatthe types of reasoning ability the psychologists were look-ing for are not needed by chemistry students.)

It is certainly true that in most undergraduate chemis-try curricula students are much more often confronted withproblems that have definite, deterministic answers than theyare with problems that may have several answers or no an-swer at all. The chief exception to this is undergraduate re-

search, which does involvestudents in questions towhich their experimentalanswer is not going to bechecked against the back ofthe book. Since undergradu-ate research has obviousbenefits in the maturation ofyoung chemists, wouldn’t it

make sense to try to make some of the same benefits avail-able to students in nonresearch courses? But how?

Nisbett et al. provide some ideas for us to try. In somecases using examples alone, or teaching general logicalrules alone, will suffice. We are at that stage in the text-books and teaching methods of many of our undergraduatecourses now. Books are full of very specific examples of howto solve relatively simple problems. Indeed, some studentsdon’t bother to read the book at all, because concentratingon the examples will make them successful on our tests. Ithink that there are many cases in chemistry teachingwhere we need to go much farther than the excellent ex-amples we already have, and Nisbett et al. reinforce thatbelief. More important than either a formal discipline oflogical rules or examples of applying those rules is the com-bination of the two: abstract training closely coupled withconcrete, real-world examples (very different from the text-book examples just mentioned) of how to apply the abstractideas in a variety of situations.

I ran the Nisbett paper by a psychologist friend of mine,and he took it one step farther. The really hard trick, afterknowing abstract rules and being familiar with examplesof applying them, is to know which set of abstract rules willwork in a new situation. (Or, from a more discipline-chauvinistic perspective, to know to which kinds of newsituations chemistry’s abstract rules will apply. Fortunatelythere are a great many.) We need to present students witha broad range of situations where they can practice skillsof choosing and applying abstract sets of rules to unfamil-iar problems. Concentrating too much on the standard, rela-tively simple “problems” in most textbooks and examina-tions is not enough. So let’s work to go beyond that increative and effective ways!

Literature Cited

1. Nisbett, R. E.; Fong, G. T.; Lehman, D. R.; Cheng, P. W. “TeachingReasoning”; Science 1987, 238, 625–631.

2. Thorndike, E. The Psychology of Learning; Mason-Henry: NewYork, 1913.

3. Brainerd, C. Piaget’s Theory of Intelligence; Prentice-Hall:Englewood Cliffs, NJ, 1978.

Editorial: Can We Teach Reasoning? Should We?

A reader’s reaction to what I wrote here in Decemberled me to a very interesting article in Science, where Nisbettet al. report psychological studies that suggest that “…evenbrief formal training in inferential rules may enhance theiruse for reasoning about everyday life events” (1). But the au-thors also quote data that imply that chemistry graduateprograms are not very effective in helping students developtheir abilities to apply statistical reasoning and logical rea-soning to unfamiliar problems.

The idea that formal study of abstract systems of rulesdevelops habits of mind that are useful in reasoning aboutconcrete problems has beenaround for a long time. Plato, forexample, argued that study ofarithmetic and geometry was ef-fective in improving reasoning,and that improving the arithmeti-cal and geometrical skills of itsleaders would serve a state well.Other formal systems, grammar,logic, and languages, were added to arithmetic and geom-etry, resulting in the classical college curriculum of the nine-teenth century—a curriculum that did not include chemis-try or other natural sciences.

The incorporation of science into the curriculum thatbegan in the late nineteenth and early twentieth centurieswas based to some extent on experimental evidence thatcast doubt on Plato’s idea that formal training in reasoningwould carry over into all aspects of a person’s intellectualand practical life. Thorndike, on the basis of empirical re-search on transfer of training effects, argued that there areno general inferential rules that apply to all disciplines (2).Instead there are highly specific empirical rules that dealwith concrete events and apply to other events only to theextent that the two have identical elements in common.Piaget agreed with Plato that people use inferential rules,but argued that these cannot be taught to any significantextent (3). Every individual develops such rules in the nor-mal course of maturation, but instruction cannot alter thatdevelopment. Both of these positions argue against the clas-sical, one-size-fits-all curriculum.

Nisbett et al. take an alternative view that is closer toPlato’s: people do use inferential rules, and such rules canbe taught, sometimes by abstract means. However, Nisbettet al. argue that the rule systems people use naturally (andthat can be taught) are pragmatic and are induced in theprocess of solving recurrent everyday problems. With respectto training in statistical reasoning they found that eitherteaching statistical rules or teaching by having studentssolve example problems would work. With respect to train-ing in conditional logic, they found that neither abstract logi-cal training nor showing subjects how to use rules to solveproblems would work alone, but when these two approacheswere used simultaneously, students learned.

To me the most interesting aspect of the Nisbett paperis also the most disturbing. Chemistry was one of four dis-ciplines within which they studied the effect of two years ofgraduate work, both on statistical and methodological rea-soning and on applying conditional logic to solve problems.Two years of graduate study did not significantly improvechemistry students’ abilities in either area, although it didimprove the abilities of medical students and psychologystudents in both areas and the abilities of law students in

…students are much more often confronted

with problems that have definite, deterministic

answers than they are with problems that may

have several answers or no answer at all.