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How We Write about Biology by Randy Moore

(The American Biology Teacher 53:388-389 1991)

Recently while grading laboratory reports I came across this abstract in a student's paper:

It was decided to do the transpiration experiment. The experiment was done by my lab group and was repeated three times. Results were obtained. These results will be discussed.

I asked the student why he had written every sentence in passive voice. He replied that, "Biologists write like this because they're objective. It's just how real scientists write." I cringed. Apparently, scientists such as Einstein, Faraday, Watson, Crick, Darwin, Curie, Lyell, Freud and Feynman - scientists who communicated their brilliant ideas by preferring active rather than passive voice - weren't "real scientists."

My talk with the student frustrated me and reminded me of one of the failings of education: our failure to teach students to communicate effectively. With no effective instruction, most students in biology classes learn scientific writing by mimicking the writing of other scientists. Since most scientists write poorly, it's not surprising that my student wrote such a horrible abstract. However, such writing isn't restricted to students; I regularly read similar writing in grant proposals and papers submitted for publication in "scholarly" journals.

In this editorial I can't discuss all the aspects of how to write effectively about biology. Consequently, I'll discuss one of the most common weaknesses of scientific writing and one of the most common complaints of biology editors: the excessive use of passive voice.

In writing, voice refers to the relationship of a verb to its subject. If the subject receives the verb's action, the sentence is written in passive voice. Passive voice is an abstract style of writing based on to be verbs such as is, was and were. Here are some examples of passive voice:

It was suggested that the experiment be terminated.

Papers are written by students.

A cracker is wanted by Polly.

The lead verbs [they are actually auxiliary verbs] in these sentence are was, are and is and identify no one responsible for the action. Passive voice typically produces unnecessarily long and weak sentences that sap readers' strength and sound pompous. Moreover, passive voice is usually unconvincing because it suggests that scientists were acted upon rather than that scientists acted. With passive voice, it seems as if writers report revelation, not information, because passive voice implies that a force - the amorphous it - guided their work.

Passive voice can be useful to writers. For example, passive voice is effective when you want to stress what was done rather than who did it, as in the sentence, "Darwin's The Origin of Species was published in 1859." Passive voice is also useful when you want to avoid accountability - that's why embarrassed politicians report that "funds were found to be missing" rather than "I stole the money." Passive voice is also useful for adding variety, softening commands, avoiding embarrassment and slowing the pace of writing and reading. However, the excessive use of passive voice produces ineffective and boring prose - prose that can be avoided by using active voice.

Active voice is a style of writing in which the subject acts. For example:

I suggested that we end the experiment.

Students write papers.

Polly wants a cracker.

James Watson and Francis Crick used active voice and a simple, personal, get-to-the-point style of writing to forcefully begin their monumental paper describing the structure of DNA: 'We wish to suggest a structure for the salt of the deoxyribose nucleic acid (D.N.A.).'

Watson and Crick knew what good writers know: that active voice strengthens writing because it improves readability, makes sentences more concise and increases understanding. No matter what you're writing about, the use of active voice almost always increases the clarity and persuasiveness of your writing. Such persuasiveness is especially important to scientists because scientific "truths" are the product of effective arguments. Why, then, do so many scientists insist on using passive voice so much?

Most scientists use passive voice either out of habit or to make themselves seem scholarly, objective or sophisticated. Scientists have not always written in passive voice. First-person pronouns such as I and we began to disappear from scientific writing in the United States in the 1920s when active voice was replaced by today's inflexible, impersonal and often boring style of scientific writing. Since then, scientists have used the anonymity of passive voice to make themselves appear as modest, passive and objective observers. This is unfortunate because passive voice greatly diminishes communication. For example, when speaking, most biologists provide information in the way that we ordinarily expect to receive it - as a narrative:

We wanted to understand how penicillin affects growth of bacteria. To do this, we grew bacteria in the presence of varying concentrations of penicillin. We learned that penicillin inhibits growth of bacteria.

Narratives such as this aren't something that any of us have to think about - we talk like this all the time. And when we aren't telling these kinds of stories, we're listening to them. However, compare this with the abstraction of passive voice:

The growth of bacteria was studied. Bacteria were grown in the presence of varying concentrations of was learned that bacterial growth is inhibited by penicillin.

Nobody in the real world communicates like this. Consequently, the insistence of many biologists {including my student) to write only in passive voice forces readers to shift into a foreign mode of communication. This makes passive voice hard to write and even harder to read because, especially when reporting experiments, it doesn't reflect what really happened and sometimes changes the substance of what we did. Nevertheless, many students and professional biologists believe that science must be written in dull, passive style. Too bad.

The notion that passive voice ensures objectivity is ridiculous because objectivity has nothing to do with one's writing style or use of personal pronouns. Objectivity in science results from the choice of subjects, facts that you choose to include or omit, sampling techniques and how you state your conclusions. Scientific objectivity is a personal trait unrelated to writing.

Contrary to the implication of passive voice, science is a personal activity done by people, not machines. The belief that using I and we somehow makes science undignified is foolish and hobbles science. After all, all research is done by someone, and every paper, book and essay lists someone as the author. Most biology editors prefer that writers use l or we to describe research. Indeed, The American National Standards for the Preparation of Scientific Papers for Written Or Oral Presentations, which includes an impressive list of organizations represented by its views, states that, "When a verb concerns action by the author, the first person should be used, especially in matters of experimental design." If the purpose of your paper is to tell what you did and observed, then the word l or we should appear at the beginning of sentences and clauses. Insisting on using verbiage such as "the authors" or "the writers of this paper" achieves no modesty and is pompous, distant and stuffy.

Biology is the great adventure of our time. Let's not suffocate it with passive, abstract writing.

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