The Principle of Anticipation requires you to "anticipate" a correct answer. Practically, what this means is that you must retrieve the answer from your own memory before it is confirmed in the lesson. It works as follows:

The lesson will pose a challenge -- perhaps by asking you, in the new language: "Are you going to the movies today?"

There will be a pause, and, drawing on information given previously, you will say:

"No, I went yesterday."

The instructor will then confirm your answer:

"No, I went yesterday."

Before Dr. Pimsleur created his teaching method, language courses were based instead on the principle of repetition. Teachers drummed words into the students' minds over and over, as if the mind were a record whose grooves wore deeper with repetition. However, neurophysiologists tell us that, on the contrary, simple and unchallenging repetition has a dulling effect on the learning process. Eventually, the words being repeated will lose their meaning.

Dr. Pimsleur discovered that learning accelerates when there is an "input/output" system of interaction, in which students receive information and then are asked to retrieve and use it.