Comparison and contrast are both centrally important forms of critical thinking. In the 1990’s a major state university found that its English Department faculty prioritized comparison and contrast much more than did other faculties within the university and that comparison and contrast were more nurtured by the university than other forms of critical thinking. Literature allows us both to compare and contrast different ways of thinking and doing, either within a work or between works of art.

Comparison and contrast unfortunately lend themselves to “invidious”  (harmfully biased) comparison or contrast. It is normally only decent and polite to avoid both. 

N.B. Invidious is not insidious. Both are negative and typically stealthy, often subtle. Insidious comes from the Latin word for an ambush. Insidious thought “lies in wait for” some concept or person to harm. So critical thinking should check itself for lying in wait, and if it is, the thinker should at least recognize the risks inherent in attempting to harm.

Where comparisons and contrasts may be contentious, it is a very wise policy to begin with an absolutely objective standard. For example, Walt Whitman is often thought of as the prophet par excellence of American democracy. However typical that idea has been, it is obviously on shaky ground if no one can define democracy or prophet.

Guises

Comparisons and contrasts at collegiate levels and above tend to look for the subtle rather than the obvious. To say that two cars are cars, for example, is a comparison not worth making. What is typically called for in comparison and contrast thinking is to see that two things are alike, despite guises that keep them appearing different or to see that two things are different, despite a common guise that keeps them appearing to be the same or very similar. Interesting comparison might compare the humor of Washington Irving in his Knickerbocker stories and Hawthorne’s humor in his Tanglewood stories. Interesting contrast might contrast Malcolm X’s sense of insular, northern black ghettoes with the cosmopolitan leadership of the Harlem Renaissance.

Thinking and writing about comparison and contrast thus takes on a special challenge with the readership. If readers do not see that two things are similar, a good comparison must somehow convince them that looking more deeply shows something worth seeing that is similar. Contrast has the same persuasive challenge only reversed.

Defining the guise that makes things appear different or that makes them look the same is a key step in good comparison and contrast thinking.

Doing Both

There is a tendency in student work particularly to assume that comparison and contrast should always be done together. A is like B in this way, and A is unlike B, really quite contrastive, in that way. The assumption seems to be that running comparison and contrast together makes for better “balance.” The writer is not so committed to seeing the similarity that the writer is blind to the differences. 

But the final effect in many cases is to make things banal, trivial, and ludicrous. If two people, despite many superficial differences, are, in fact, identical twins, raised in the same family with the same standards and goals, saying that the two are similar and yet different can be non-thinking rather than critical thinking. Much more interesting and revealing may be to go in depth on comparison alone, to show that the one twin in medicine actually is exercising the same standards and trying to achieve the same goals as the other twin who chose the professoriate as career. A literary example might be showing that Shakespeare in Macbeth uses much the same rhetoric that characterizes Julius Caesar.

Purpose

Too often, students are writing comparison and/or contrast papers simply because that is the assignment. They have absolutely no commitment to any higher purpose than to hand in a paper that does the assignment. Good comparison and contrast thinking has some guiding purpose—in the sample above, the writer may have a purpose of showing that standards always have to be modified to meet occupational demands. 

Any two things in the world can be compared: Hitler and an octopus can be compared—and  maybe should be.

Any two things in the world can be contrasted: Stalin and Lenin, though often spoken of in the same breath, had very different characters as leaders.

If we take seriously that anything can be compared or contrasted, then the purpose of the comparison or the contrast becomes of quite prominent importance for what we note and what we gloss over.

See also Perils of Negative Thought.

Further reading on comparison and contrast: 

How to Write a Comparative Analysis 

What Is Comparative Analysis?

Comparative Criticism