1. Definition

From rhetorical device to cognitive device 

1) The classical view sees metaphor as a kind of decorative in addition to ordinary language, a rhetorical device that makes language use colorful. 

2) Another view of metaphor, which has become more influential in the past two decades, holds that metaphors are a cognitive device. Metaphor is an essential element in our categorization of the world and our thinking process. 

3) Cognitive linguistics has shown that metaphor is not an unusual or deviant way of using language. The use of metaphor is not confined to literature, rhetoric and art. It is actually ubiquitous in everyday communication.

2. The components of metaphors 

1) Target domain – tenor (abstract and novel) 

2) Source domain – vehicle (concrete and familiar)

The transference of properties of the source domain to the target domain is referred to by some cognitive linguistic as mapping.

3. Features of metaphors

There are three main features: systematicity, creation of similarities, and imaginative rationality.

1) Metaphors are systematic precisely because they are conceptual in nature.

2) Metaphors can create similarities between the two domains involved. We use metaphor to create similarities and correlation between two separate categories, so that we can understand on kind of experience in term of another.

3) Metaphors are also characterized by imaginative rationality. They unite reasoning and imagination. Metaphors as a form of reasoning by analogy involve categorization, entailment and inference. By metaphors we understand one kind of thing in terms of another kind of thing.