Metaphysical poetry is characterized the most by the use of metaphors and comparisons. The comparisons achieve the end of analyzing an argument or an idea that's presented in the poem and logically reaching a conclusion  - for eg, the idea of a person being in love with another person may be presented as a series of arguments and  comparisons. These comparisons are often of very unusually dissimilar nature - or as said by Samuel Johnson: 'yoked by violence together'.

Conceit is a very important aspect in metaphysical poems. Conceit is generally a lofty, too-stretched comparison between the spiritual nature or emotional state of being of a person to something physical. Metaphysical conceit is more intellectual in nature than petrarchan conceit, which generally compares a lover's anguish to things in nature, such as a lover's sigh carrying such force as to move ships. A metaphysical conceit, instead of being a fleeting comparison made, can form the entire structure of a poem.

Metaphysical poetry treats human experiences and emotions in terms of analytical, intellectual rather than emotional terms, frequently becoming one long reasoned argument. For instance, if the poet is discussing his love for a lady or his love for God, instead of saying "I love thee," offering direct emotional expression to his feelings, he will analyze his love, argue his way through a logical presentation (in essence, try to discover a more intellectual way of making an emotional presentation).

Dryden and Samuel Johnson (who coined the term 'metaphysical poets' to put poets of 17th century who wrote in such fashion under an umbrella term) were not in favour of the excessive intellectuality in metaphysical poems. When Johnson used the term 'metaphysical' poetry, it was in a contemptuous sense that he used it. They found the comparisons used in metaphysical conceit too far fetched and obscure and mentally exhaustive. As for the metaphysical poets, they prided in the intellectual way in which they presented their argument for the establishment of the core idea of their poems.

Metaphysical poets were therefore ignored during their time. Poets like Andrew Marvell however did find momentary acceptance in the ensuing Age of Enlightenment when writers like Alexander Pope and J. Swift recognized the intellectual reasoning and sharp satire in his works, and adapted the same in their works.

Later, in the age of Romanticism, of course, the hard line of reasoning and intellectuality of metaphysical poets were forgotten or ignored in the light of new-found love and embracing of individualism and joyful disregard for reason. Then they were finally acknowledged for what they were with the dawn of New Criticism of 20th century, by writers like T.S. Eliot with his essay 'The Metaphysical Poets' (1921).

'Dissociation of sensibility' is a term coined by T.S. Eliot, saying that he felt the poems following the English Civil War of 17th century tended to separate emotions from intellectual reasoning. He is of the opinion that Donne however viewed this separation of emotions from intellectual reasoning to be a hindrance in the development of poetry, and Donne embraced this combination of intelligence and emotions in his poetry. He presented emotions as argumentative reasoning.

Metaphysical poets strove to analyse emotions, and not simply express them, as the Elizabethan poets did.

Metaphysical poems were concerned with love, the meaning of love, sensual things, existence and reality, and man's relationship with God and the Universe and the ultimate nature of reality.

Metaphysical poetry shows use of Neo-Platonism to show the relationship between the soul and the body.

The argumentative nature of metaphysical poetry lies in the fact that it persuades the reader to believe the bizarre comparisons and conclusions it makes. The persuasion is done by a series of rhetorics and line of thoughts which leads to the ultimate conclusion. 

This step by step logical persuasion gives it a sense of being intellectual and sound in the reasoning it makes, despite the reasoning or the idea that it presents being inherently bizarre.