Deductive vs Inductive Reasoning/Writing
Deductive Reasoning
This is what you were taught by Mrs. Brown in your high school English class. You probably were
asked to do this quite a bit in your history and civics classes as well. In most cases, you were taught to
come up with a point that you intend to make, and to put it into one sentence called the thesis
statement. You would then come up with three more sentences that would support your thesis
statement with three specific points. With these four ingredients, you wrote a straightforward fiveparagraph essay, and hopefully got an A for your effort. Of course, for the purposes of writing an
epinion, you may have less, or more, than three examples to present, and hopefully you have more.
The five paragraphs would be as follows. The first paragraph would introduce some introductory
information about your subject. For example, if you were writing a book report for your high school
class, a brief synopsis of the book's purpose and contents (or plot if it is fiction) would do, and the
thesis statement would come at the end. The second paragraph then would start with your first point
statement, and you would fill up the rest of the paragraph with facts to support your point. In a book
review, they could be specific quotes from parts of the book. The paragraph would end by reiterating
the point that was to be made. The third and fourth paragraphs repeat the same with the other two
points you would be attempting to make. The fifth, and final paragraph, would start with a revised
version of the thesis statement, tie together the three points you had made in the middle three
paragraphs, and lead the reader into new insights by introducing minor new thoughts or asking a few
questions. Very straight forward way to write an essay, or an epinion for that matter.
For many writers, and for many types of reviews, this is the way to go. It is logical, the thought process
is easy to follow, and even for those who do not have the time to completely read your epinion, the key
points would be loud and clear. And you were drilled in this in high school, so you already know how to
do it. Most of my reviews, in fact, do follow this format more or less. For example, when I write a review
on a city, I start with introductory information about the city such as its history, then state my feelings
regarding the city, which would be my thesis. Specific points follow, as I discuss the city's
transportation system, cultural life, attractions, and safety, among others, then I end by tying up these
points together and issuing a verdict.
I read many music reviews, and I see that many teenage girls are itching to review the latest albums
from their idols such as Britney Spears and N'Sync. Unfortunately, most of them are one-paragraph
rants on how great their idols are, with little to support their point. I highly suggest that you think over
what you specifically like about the album, and come up with concrete examples. Go through your
English class notebooks, and come up with a thesis statement that says how you feel about, say,
N'Sync's No Strings Attached, then support your feelings with paragraphs that respectively focus on
specific aspects, such as lyrics, vocal work, arrangements, and stylistic influences. Do these well, and
you might as well get me to go out and try the album myself; that is called a successful epinion.
The downside to the deductive reasoning is that it is too rigid and structured, too predictable. Read on
for an alternative approach.
Inductive Reasoning
When I first started college, I took a writing class as part of freshman curriculum. The first thing I was
taught was: "Forget the five-paragraph monster!" The five-paragraph monster, of course, refers to the
deductive reasoning essay I described above. Okay, if the five-paragraph monster doesn't work, then
what would? Then I was drilled in a new kind of writing - inductive reasoning.
Deductive reasoning is "deductive" because you make a point and use your writing to prove, or
deduce, that point. Inductive reasoning is different, as you first start by laying out some key facts, then
delay tying them up together until the very end. Instead of proving your thesis statement, you are
building it. This is especially good when you start writing with a certain conclusion in mind, but your
thought processes used during the actual writing start to drift you into a different conclusion.
Again, say I am writing another city review, this time about a city I have a negative impression of, such
as Amsterdam or Seoul. These cities nevertheless have some very special charms of their own, and I
would start by discussing some of the better moments, such as visiting Anne Frank House or an
ancient palace. Then I go into my concerns, such as safety, and save the conclusion until the end; my
conclusion ends up slightly different from my intentions by putting these cities in a slightly more
positive light, but since it was derived from the various arguments I had made during the course of the
writing, it flows right in. If I were to write a deductive essay, it would probably start out with a negative
thesis, and I may have to strain here and there, even leaving some positives out, to prove my negative
thesis. Or, I could change to a better thesis after the writing is done, but heavy editing of the
introduction may be necessary, and a smooth, coherent flow of ideas may be not only difficult, but
sometimes impossible. Hence the inductive style works much better in these cases, with the result that
I end up with a balanced, informative review instead of one influenced by my personal feelings.
The power of the inductive essay is that it is flexible. It does not have a fixed structure that a deductive
essay has. You may start writing with only the most basic of ideas and plans, but it has the power to
develop into an excellent, coherent opinion that consistently gets HR. Also, by its very nature, an
inductive essay can have surprises; you may even want to interject some humor here and there, which
would not be so nice in a deductive essay because the thesis and your points give the humor away
beforehand. On the other hand, a good inductive essay is difficult to write; it can easily disintegrate into
a jumble of nonsense with no coherence. This is why you learn inductive reasoning in college, as
opposed to high school.
Conclusion
Use these two types of reasoning well, and you will have an excellent, clear, coherent opinion that will
garner HR more than you could ever imagine. Know the strengths and weaknesses of each type, and
use them to your advantage. Have fun writing!
Source:
“Deductive vs. Inductive Reasoning.” Epinions.com. SWHS. 7 February 2007.
http://www0.epinions.com/user-review-7878-86D6178-397D025C-prod1