It’s easy to confuse the words imply and infer. To help you sort them out, let’s first define them.
imply: v. to indicate or suggest
infer: v. to derive or conclude by reasoning
The confusion comes because the words are similar in construction and because they address the same idea from different angles. They are not so much opposites as complements. They are the two sides of a single action. Think of a pitcher throwing a ball to a catcher. Implying is like pitching and inferring is like catching.
A speaker or writer implies. He says something without literally saying it. It is an action initiated by the sender of the message. The listener or reader infers. He hears something that may or may not have been intended, but seems to be hinted at indirectly. Inferring is an action by the recipient of the message. The illustration below might help you picture it.
Here’s an example:
Charlie: I don’t understand this math problem.
Stanley: You don’t? A third-grader could do it.
Charlie: Are you saying I’m dumb?
Stanley: I guess I am.
In this dialogue, Stanley is implying; Charlie is inferring.
The noun forms of these words are implication and inference. So, you might also say that Stanley is making an implication and Charlie is making an inference. Get it?
Another way of thinking about it is that implying means putting a suggestion into a statement and inferring is getting a suggestion out of a statement.
Now, we must be careful with these words. The pitcher-catcher analogy breaks down a little bit when you consider that while a pitcher can pitch without anyone to catch (he’d have to fetch his own ball), a catcher cannot catch what has not been thrown to him. This is not the way implication and inference works.
It’s possible for someone to make an implication without anyone noticing. The listener or reader might fail to “catch the implication” or make the correct inference. But it’s also possible for someone to make an incorrect or unfair inference. Perhaps Stanley did not intend to suggest that Charlie is dumb. If so, Stanley should be more careful with his choice of words, because, even if he implied something unintentionally, his choice of expression led Charlie to infer something negative.
So, is there an easy trick to keeping imply and infer straight?
Maybe it will help to remember that in most cases, implying must come before inferring (like pitching comes before catching), and m comes before n in the alphabet.