GMAT Critical Reasoning: Inference vs Assumption

Inference vs Assumption

Let’s start exploring this subject with a pedantic question, “Who authors a GMAT Argument?” You may be thinking that what a stupid question is this. Obviously, the Author of the Argument authors it. Exactly, the Author of a GMAT Argument authors the Argument which consists of two parts a premise and a conclusion. The Assumption is the third invisible part of the argument that connects the premise to the conclusion. The Assumption remains unstated because it is there in the mind of the author who has constructed the argument. He doesn’t state that it explicitly in the argument because he feels no need to do so. For him, it is very much implicit in the argument and will be evident to anyone who carefully reads the argument. Therefore, An assumption originates in the mind of the author who formulates the argument.

Inference vs Assumption

In stark contrast to  Assumption which is a part of an Argument, Inference is something that the reader gathers from the argument after reading it. A correct Inference will be one which will be true on account of whatever is written in the Argument. I will make my point clear with the help of an example. Let say I make the following statement in public about a person standing before me, “His hair is wet”. What all inferences can you draw from my statement? You may have drawn anyone/all of the following inferences from the statement that I made about that person.

He just had a shower.
Someone poured a bucket of water upon him.
He got drenched head to toe by rain.

But from the statement that I have made can you be hundred percent sure about anyone of these possibilities. Of course, you can’t be. Therefore the only valid inference that you can draw from my statement is that his hair is not dry.

Before I conclude my argument I would like to state that negation of the assumption of an argument makes its conclusion meaningless because the assumption is taken by the author of the argument. Whereas negation of inference has no such effect upon the argument because Inference is drawn by the reader of the argument.

Read here: GMAT Critical Reasoning: Inference vs Assumption Example

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