Analytical Writing for Science and Technology
Copyright © 1996 by T. M. Georges.

Lesson 17

Step 4 to More Informative Paragraphs -- Arrange Your Ideas in a Logical Sequence


One of the most frequent complaints about scientific and technical writing is that ideas aren't arranged logically. Thoughts are often thrown in at random, with no particular connection with with what has come before or with what follows. This is particularly confusing when the ideas are complicated and technical. The way you order ideas is not only a way to hold your readers' interest, it's yet another way to emphasize what's important and suppress the incidental.

You may not realize that there are different logical sequences, or frameworks, in which to present your information. Without thinking, many people present things chronologically, as though to reproduce the way events actually happened. This is especially tempting after you have labored for months or years to produce your final product or result. You might want your readers to appreciate every painful hurdle and obstacle you encountered along the way.

Sadly, however, few of your readers care. In fact, you do them a great disservice to drag them over that same tiresome ground with you. Instead, think of all your hard work as saving them the trouble.

Here are just a few examples of logical sequences that you might find useful in your own writing. Write in the blank following each one a couple of examples of subjects that might best be organized that way:

A TEMPORAL SEQUENCE: for emphasizing the time relations among things or events:


A SPATIAL SEQUENCE: when you want your reader to see the way different aspects of your subject are spatially interrelated or lie in contrast:


STEPS OF A PROCESS: when you want to focus on a process itself, not the end result:


INCREASING COMPLEXITY: a sequence that leads your readers gently into a complex subject:


DECREASING ORDER OF IMPORTANCE: when you want to tell your readers that something new has happened and why they should be interested -- then fill them in on the details:


Whatever sequence you select for your purpose and audience, a good way to make sure that your sequence is, in fact, logical is to make sure the connectives are there. If they aren't, and if you can't work them in, let that be a signal that your sequence is not a logical one.

Here's an exercise to make you think about the right logical sequence for presenting various kinds of information. Write in the blank following each subject the sequence you would choose from the list above. Make up a sequence of your own, if you think it is more appropriate. Some complex subjects require more than one sequence, one nested inside another. Mention such cases, where appropriate. Also be aware that you might use different logical arrangements of the same material when writing for different audiences.

A memo telling the programming staff how to submit jobs to the new computer

A press release describing your new video camera

A proof of a mathematical theorem

A technical report documenting a computer program for controlling a milling machine

A proposal to the National Science Foundation asking them to fund your genetic research

A description of improvements to a steelmaking process

A summary of the results of the latest census

A journal paper describing your discovery of a new drug for curing acne

A technical report analyzing the effects of the solar cycle on climate

A trip report

An instruction manual for your word-processor

A report to the President on national unemployment statistics

Notice that there are no ironclad "right" answers to these questions. The way you arrange ideas for one audience may not work for another. In the end, you have to decide which arrangement best matches your readers' needs. You will be better equipped to do that if you keep all the choices in mind, rather than being locked into one. Examine each arrangement and assess how each one serves your purpose in writing.


When you find the most logical framework for your message, your readers will feel comfortable reading it, because the reasoning flows naturally. An easy way to test for logical flow is to look for and try to insert the logical connectives.

Next we ask how personal you should get in your scientific and technical writing. This sticky question is hotly debated wherever scientific and technical writing is taught.

-- End of Lesson 17 --

Beginning of Lesson 17 || Contents || Go on to Lesson 18