A common place remark

One word substitute is Platitude.

Dialogue: a conversation between two or more people as a feature of a book, play, or film.
Platitude: a remark or statement, especially one with a moral content, that has been used too often to be interesting or thoughtful.
Epigram: a pithy saying or remark expressing an idea in a clever and amusing way.
Statement: a definite or clear expression of something in speech or writing.