In a previous blog post, I wrote about reasoning as a prerequisite to organizing and wording arguments in a persuasive speech. We teach the important principles of parallelism and alliteration in our Speech Class Refresher program. You can read that post by clicking here.
In that post, I focused upon deductive reasoning, of which there are two types: syllogistic and enthymematic.
I did not mean for anyone to interpret that post to think that I do not also believe in inductive reasoning in a persuasive speech.
There are four types of inductive reasoning:
by example – give an incident that illustrates the argument; note that an extended example is a case or story – “President Ford introduced WIN – whip inflation now – as a major initiative to turn around economic conditions.”
by cause – show that there is a factor that is a force that produces some effect; always start with the effect – if it is good, put more resources behind the causal factor; if it is bad, minimize or eliminate the factor – “Illegal immigrants have helped businesses maintain steady employment wages.”
by analogy – show that what is true in one case is also true in another; the underlying assumption is that the two items being compared are highly similar – “Truman ended the conflict with Japan by dropping two nuclear bombs. If Trump does the same with North Korea, we will end any conflict we have with them.”
by sign – make an observation that infers some effect or outcome – since it depends upon an inference, it is the weakest type of inductive reasoning – “The current construction that we now see of new homes and apartment complexes in our city indicate that our local economy is getting stronger.”