Titus Lucretius Carus, known as Lucretius (99 BCE - 55 BCE), was a first century Roman poet and philosopher, whose only surviving work is his prescient, didactic poem, titled Of the Nature of Things (De Rerum Natura). His work, spanning six books painstakingly transcribed on papyrus rolls and stored in circumspect for centuries, explains the tenets of Epicureanism, a belief in striving for pleasure without pain (a form of hedonism), seeking knowledge of the workings of the world (atomism), and understanding the nature of the mind and soul to achieve a state of tranquility in this life, which is the only one that exists. The Church violently opposed Epicureanism as the antithesis of Christian beliefs that to ensure a glorious after-life, man must forego all pleasures in this life, and subject the body to pain, including earning penance, some believed, through self-flagellation. Epicurean and hedonist pursuits of intellectual ideas, including Lucretius' work, were shunned and destroyed throughout many centuries (and popes) as a direct threat to the faith-based rules defined by the Church.
Engraving above by Michael Burghers, frontispiece of Thomas Creech's Of the Nature of Things, 2nd and 3rd editions, 1682-3.
Lucretius' work was thought to be lost during the Middle Ages, as were the concepts of Epicureanism, pleasure and intellectualism, until the advent of the Age of Enlightenment, when it was revived, along with Epicureanism. For an interesting perspective on Lucretius' work, read The Swerve: How the World Became Modern (2011) by Stephen Greenblatt