The metaphysical poets (John Donne is a striking example) were characterised by the use of their poetry to puzzle and perplex, rather than just to create beautiful or emotional verse. John Donne for example was a trained lawyer and his mathematical, scientific, philosphical and mathematical skills of presenting ideas and complex theories in beautiful evocative language come across in most of his poems. This type of poetry is a joy to read, for it presents ideas as well as images and is very though-provoking. The ideas so presented became known as 'conceits.'
One famous example is John Donne's presentation of the union between man and woman as being similar to the blood ingested from two people by a flea - they are intermingled. He presents it to a sweetheart as a reason why she should accept his advances in a more physical way.