The phrase put two and two together is an idiom. We will examine the meaning of the idiom put two and two together, where it came from, and some examples of its use in sentences.
To put two and two together means to collate the information that one has and draw a conclusion or arrive at an answer. To put two and two together means to infer something from the data at hand, to make a guess based on the available information. The expression put two and two together has been in use since the mid-1800s and is as popular as it has ever been. The idiom is an abbreviation of a longer maxim that dates back to the 1600s: “The notion is as clear as that Two and Two makes four.” This sentiment appears in a book of essays, Essays on Several Moral Subjects in Two Parts, published by the theater critic, Jeremy Collier, in 1697. Today, the expression put two and two together may be used humorously by adding an addendum like, “and got five.” This is a way to say that one came to an erroneous conclusion by a poor interpretation of the available data.
“I guess no one had ever put two and two together and realized the severity of the issue,” Lynn said. (The Washington Post)
“She had never put two and two together, so I said, ‘You know, that’s Daddy’s voice’ . . . Maui starts singing, and then I start singing, and within 10 seconds she’s trying to put a pillow over my mouth and says, ‘You’re ruining the song!’ ” (New York Times)
“The defendant immediately produced a handgun, at which point (the semi driver) put two and two together and realized he had just been shot at,” records say. (The Seattle Times)