Theologian in the context of "Understanding"

A scientist is a expert who conducts scientific research to advance knowledge in science.

In classical antiquity, there was no real ancient analog of a modern scientist. Instead, philosophers engaged in the philosophical study of nature called natural philosophy. Though Thales (c. 624–545 BC) was arguably the first scientist for describing how cosmic events may be seen as natural, not necessarily caused by gods, it was not until the 19th century that the term scientist came into regular use: it was coined by the theologian, philosopher, and historian of science William Whewell in 1833 to describe Mary Somerville.

Sir Isaac Newton (/ˈnjuːtən/ ; 4 January [O.S. 25 December] 1643 – 31 March [O.S. 20 March] 1727) was an English polymath active as a mathematician, physicist, astronomer, alchemist, theologian, author, and inventor. He was a key figure in the Scientific Revolution and the Enlightenment that followed. His book Philosophiæ Naturalis Principia Mathematica (Mathematical Principles of Natural Philosophy), first published in 1687, achieved the first great unification in physics and established classical mechanics. Newton also made seminal contributions to optics, and shares credit with German mathematician Gottfried Wilhelm Leibniz for formulating infinitesimal calculus, though he developed calculus years before Leibniz. Newton contributed to and refined the scientific method, and his work is considered the most influential in bringing forth modern science.

In the Principia, Newton formulated the laws of motion and universal gravitation that formed the dominant scientific viewpoint for centuries until it was superseded by the theory of relativity. He used his mathematical description of gravity to derive Kepler's laws of planetary motion, account for tides, the trajectories of comets, the precession of the equinoxes and other phenomena, eradicating doubt about the Solar System's heliocentricity. Newton solved the two-body problem and introduced the three-body problem. He demonstrated that the motion of objects on Earth and celestial bodies could be accounted for by the same principles. Newton's inference that the Earth is an oblate spheroid was later confirmed by the geodetic measurements of Alexis Clairaut, Charles Marie de La Condamine, and others, convincing most European scientists of the superiority of Newtonian mechanics over earlier systems. He was also the first to calculate the age of Earth by experiment, and described a precursor to the modern wind tunnel. Further, he was the first to provide a quantitative estimate of the solar mass.

Xenophanes of Colophon (/zəˈnɒfəniːz/ zə-NOF-ə-neez; Ancient Greek: Ξενοφάνης ὁ Κολοφώνιος [ksenopʰánɛːs ho kolopʰɔ̌ːnios]; c. 570 – c. 478 BC) was a Greek philosopher, theologian, poet, and critic of Homer. He was born in Ionia and travelled throughout the Greek-speaking world in early classical antiquity.

As a poet, Xenophanes was known for his critical style, writing poems that are considered among the first satires. He composed elegiac couplets that criticised his society's traditional values of wealth, excesses, and athletic victories. He criticised Homer and the other poets in his works for representing the gods as foolish or morally weak. His poems have not survived intact; only fragments of some of his work survive in quotations by later philosophers and literary critics.

Isidore of Seville (Latin: Isidorus Hispalensis; c. 560 – 4 April 636) was a Hispano-Roman scholar, theologian and archbishop of Seville. He is widely regarded, in the words of the 19th-century historian Charles Forbes René de Montalembert, as "the last scholar of the ancient world".

At a time of disintegration of classical culture, aristocratic violence, and widespread illiteracy, Isidore was involved in the conversion of the Arian Visigothic kings to Catholicism, both assisting his brother Leander of Seville and continuing after Leander's death. He was influential in the inner circle of Sisebut, Visigothic king of Hispania. Like Leander, he played a prominent role in the Councils of Toledo and Seville.

Ramon Llull TOSF (/lʌl/; Catalan: [rəˈmoɲ ˈʎuʎ]; c. 1232 – 1316), sometimes anglicized as Raymond Lully, was a Mallorcan Catholic philosopher, theologian, poet, missionary, apologist and former knight. He invented a philosophical system known as the Art, conceived as a type of universal logic to prove the truth of Christian doctrine to interlocutors of all faiths and nationalities. The Art consists of a set of general principles and combinatorial operations. It is illustrated with diagrams.

A prolific writer, he is also known for his literary works written in Catalan, which he composed to make his Art accessible to a wider audience. In addition to Catalan and Latin, he also probably wrote in Arabic (although no texts in Arabic survive). His books were translated into Occitan, French, and Castilian during his lifetime.

Jerome (/dʒəˈroʊm/; Latin: Eusebius Sophronius Hieronymus; Ancient Greek: Εὐσέβιος Σωφρόνιος Ἱερώνυμος; c. 342–347 – 30 September 420), also known as Jerome of Stridon, was an early Christian priest, confessor, theologian, translator, and historian; he is commonly known as Saint Jerome.

He is best known for his translation of the Bible into Latin (the translation that became known as the Vulgate) and his commentaries on the whole Bible. Jerome attempted to create a translation of the Old Testament based on a Hebrew version, rather than the Septuagint, as prior Latin Bible translations had done. His list of writings is extensive. In addition to his biblical works, he wrote polemical and historical essays, always from a theologian's perspective.

Protestants were executed in England under heresy laws during the reigns of Henry VIII (1509–1547) and Mary I (1553–1558), and in smaller numbers during the reigns of Edward VI (1547–1553), Elizabeth I (1558–1603), and James I (1603–1625). Most were executed in the short reign of Mary I in what is called the Marian persecutions. Protestant theologian and activist John Foxe described "the great persecutions & horrible troubles, the suffering of martyrs, and other such things" in his contemporaneously-published Book of Martyrs.

Protestants in England and Wales were executed under legislation that punished anyone judged guilty of heresy against Catholicism. Although the standard penalty for those convicted of treason in England at the time was execution by being hanged, drawn and quartered, this legislation adopted the punishment of burning the condemned. At least 280 people were recognized as burned over the five years of Mary I's reign by contemporary sources.

Peter Abelard (12 February 1079 – 21 April 1142) was a medieval French scholastic philosopher, leading logician, theologian, teacher, musician, composer, and poet.

In philosophy he is celebrated for his logical solution to the problem of universals via nominalism and conceptualism and his pioneering of intent in ethics. Often referred to as the "Descartes of the twelfth century", he is considered a forerunner of Rousseau, Kant, and Spinoza. He is sometimes credited as a chief forerunner of modern empiricism.