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Building an argument

Learn more about how to build strong arguments using different types of reasoning

Deductive and inductive reasoning

When you start building an argument, you need to decide whether you're going to use deductive or inductive reasoning to prove your point.

Deductive reasoning

Deductive reasoning works from the more general to the more specific. Sometimes this is informally called a "top-down" approach. We might begin with thinking up a theory about our topic of interest. We then narrow that down into more specific hypotheses that we can test. We narrow down even further when we collect observations to address the hypotheses. This ultimately leads us to be able to test the hypotheses with specific data -- a confirmation (or not) of our original theories. (Trochim, 2020, para. 2)

Inductive reasoning

Inductive reasoning works the other way, moving from specific observations to broader generalizations and theories. Informally, we sometimes call this a "bottom up" approach (please note that it's "bottom up" and not "bottoms up" which is the kind of thing the bartender says to customers when he's trying to close for the night!). In inductive reasoning, we begin with specific observations and measures, begin to detect patterns and regularities, formulate some tentative hypotheses that we can explore, and finally end up developing some general conclusions or theories. (Trochim, 2020, para. 3)

What's the difference?
When deciding whether to use inductive or deductive reasoning, keep in mind that "inductive more open-ended and exploratory, especially at the beginning. Deductive reasoning is more narrow in nature and is concerned with testing or confirming hypotheses" (Trochim, 2020, para. 4),


Trochim, W. M. K. (2020, March 10). Deduction & induction. Research methods knowledge base.