If and whether are fascinating but tricky words. Both are conjunctions, and sometimes they mean the same thing. Sometimes.
Webster’s New World Dictionary includes this definition for both words: “used to introduce an indirect question.” In that case, you can use the terms interchangeably without changing the gist of the sentence:
- Ask if she was pleased with the delivery process.
- Ask whether she was pleased with the delivery process.
Sometimes, a writer will use if or whether to express a condition. The two words take on similar but slightly different meanings in conditional clauses. In conditional clauses, if means “on condition that; supposing that,” whereas, whether often means “in either case that,” so that the clause includes alternatives.
Here are some examples where the two words are not interchangeable:
- If they needed more time, they should have planned accordingly.
- Whether you choose to handle the project in-house or outsource it, you will still need to meet the deadline.
- He will push on, whether he feels happy or sad.
Often, you’ll see the alternative or not used in conjunction with whether: whether or not. Often, the or not is not necessary, unless you intentionally wish to stress the alternative. Consider these statements:
- Evaluate whether your corporate culture is well-suited to forming alliances.
- It is difficult to determine whether the company will choose to invest in a new solution.
- Whether you like the color or not is irrelevant.
Denise C. Baron is a director of global communications with Merck & Co.