え、そうですとも。

English Translation

Yes, that is most certainly so.

is this translation pair correct? What role does とも play in this sentence?

@ericaw
The Japanese sentence has a connotation like this:

Wow, what a surprise! I thought that everybody knows such an obvious thing. But apparently you didn’t know of it or do have a different opinion/observation.

The interjection is more commonly spelled as えっ、with a glottal stop than え、. It suggests that the speaker faces an unexpected contradiction.

  • えっ、そうです。

  • えっ、そうですとも。

  • えっ、そうですけど。

These three sentences sound natural, but have slightly different connotations.

とも makes the speaker’s argument a bit stronger. “Yes, that’s the truth or common sense, and nothing else” is the nuance. “Definitely/certainly” as an adverb is the meaning.

けど sounds a bit feisty. It depends on the speaker’s tone of voice and accent, but it is sometimes interpreted as “You moron. Didn’t you know such a thing? Do you have any objection to my opinion?”

Another example with とも is:

A: Would you like to participate in the next meeting? B: Yes, definitely! = もちろん、行きますとも!

Please keep in mind that とも sounds a bit old-fashioned. I don’t usually say this phrase.