What is the difference between ought and should Hmmm....?

Answer 1

In common usage, the difference is one of specificity.

SHOULD = A nonspecific suggestion

For example:

You should get your hair cut.

In this example, no restrictions (such as the style of cut) are imposed on the suggestion.

OUGHT = A specific suggestion (usually a "best practice")

For example:

You ought to wear black to the funeral.

In this example, the suggestion is meant to express what is appropriate.

The way we speak, though, is not always the way we shouldspeak. For example, "should not" (or "shouldn't") is not a correct phrase, as the use of "not" is imposing a restriction. We say, "You should get a haircut, but you shouldn't get a mullet." The correct sentence is, "You should get a haircut, but you ought not get a mullet." You probably won't hear that very often.