In this project we investigated adults‘ concept of lying. In particular, we asked (i) if it is possible to lie by using so-called presuppositions, and (ii) if implicatures that are believed to be wrong, are perceived as a lie. In other words: is it possible to lie by posing a question, or by saying something that is not literally wrong but implies something that is believed to be false? According to the prevailing philosophical and psychological theories, this is not possible. In our empirical research, however, we found that questions can be regarded as a lie, if they contain presuppositions that are assumed to be wrong: For instance, the question „Will you come to Anna’s party on Saturday?“ is judged as a lie if the questioner knows that Anna will not have a party but wants the listener to believe that there is a party. Additionally, we also found false implicatures can be perceived as lies. Consider the following example: a jealous man asks his girl-friend if she has met her former boy-friend, and she replies „He had a bad flu for the last two weeks“; the answer is not false, but is considered a lie if the flu did not stop the two from meeting secretly and Anna made this statement to make her current boy-friend believe that she has not met her former boy-friend recently.