According to Cruse (1986) and Saeed (1997), words often have connotations in meaning. Unlike the sense of a word, which is an essential part of it, connotations are not always present. Connotations can differ according to a person's attitudes. For example, the word "mathematical" might have quite different connotations depending on a speaker's experience with the subject at school: "that's very mathematical way of looking at it" could express either a positive or a negative evaluation. Connotations also differ according to the linguistic or speech context. For example, if the term "mathematical" is used in reference to someone's approach to life or social relations, a negative evaluation would probably be attached; but it could express something positive in a description of a piece of baroque music.