Antithesis occurs when contrasting ideas are expressed in close proximity with the effect of both highlighting the contrast and balancing the opposing elements. Writers typically use parallel structure in the contrasting phrases.

Antithesis derives from the Greek words anti, meaning “against,” and the word tithenai, meaning “to set, to place.”

The opening line of Charles Dickens’s A Tale of Two Cities makes use of antithesis:

It was the best of times, it was the worst of times, it was the age of wisdom, it was the age of foolishness, it was the epoch of belief, it was the epoch of incredulity, it was the season of Light, it was the season of Darkness, it was the spring of hope, it was the winter of despair, we had everything before us, we had nothing before us, we were all going direct to Heaven, we were all going direct the other way…

Note how Dickens uses antithesis extensively through this opening passage by setting antonyms in opposition to one another: best and worst, wisdom and foolishness, belief and incredulity. The overall effect achieved is one of extremes and potential for just about anything.