Quotes from Karen Sullivan

Conceptual metaphors generally 'outlive' the specific words and expressions that involve them.

If we know how metaphors work on a conceptual level, we can control their effects. We can avoid using metaphors that are confusing or distracting, and we can design metaphors that do exactly what we want. When we encounter metaphoric language, we can analyse what makes it effective or not. We can avoid being manipulated by subconscious metaphors, and we can accept the benefits of a metaphor while rejecting any aspects we find unhelpful or inaccurate.

In general, the specific words in metaphoric language are less important than the concepts that the metaphors are comparing. Critics often pay attention to metaphoric words instead of concepts, simply because words are easier to identify. It's straightforward to decide that a metaphor includes the word like and therefore is a simile. It's harder to pinpoint what's wrong with lightning that pirouettes or what's interesting about a window that resembles an eye.

all humans are given the same set of primary-metaphor building blocks, but different language and cultural groups put the blocks together in different ways. Some individuals even force the blocks together in ways that don't fit – which is the major reason we get mixed metaphors.

The 'death' of a metaphor is the loss of a connection between a metaphor and a specific word, not the loss of the conceptual metaphor itself. 'Dead' metaphors are words and phrases that were previously metaphoric, not conceptual metaphors that have disappeared. Conceptual metaphors generally 'outlive' the specific words and expressions that involve them.

Mixed metaphors with two source domains that don't make sense together, […] are the structures that most deserve the name 'mixed metaphors'.

On questions relating to the human condition, no single metaphor has all the answers.

Whether metaphors are strung together like separate beads on a string, or kneaded together into a compound, it's important that we can use more than one of them.

The fact that metaphors can sleep and wake is both bad news and good news for speakers and writers who want to avoid mixed metaphors. The bad news is that when a metaphoric word or phrase is sleeping for us, we probably won't notice if we use the word or phrase in ways that are inconsistent with its source-domain meaning.