Thomas, a political writer, was born at Malmesbury in 1588. He was the son of a clergyman; and having completed his studies at Oxford, he was afterwards governor to the eldest son of William Cavendish earl of Devonshire. He travelled through France and Italy with that young nobleman, and at length applied himself entirely to the study of polite literature. He translated Thucydides into English; and published his translation in 1628, in order to show his countrymen, from the Athenian history, the disorders and confusions of a democratical government. In 1626 his patron the earl of Devonshire died; and in 1628 his son died also: which loss affected Mr Hobbes to such a degree, that he very willingly accepted an offer made him of going abroad a second time with the son of Sir Gervase Clifton; whom he accordingly accompanied into France, and stayed there some time. But while he continued there, he was solicited to return to England, and to resume his concern for the hopes of that family to whom he had attached himself so early, and to which he owed so many and so great obligations. In 1631, the countess dowager of Devonshire desired to put the young earl under his care, who was then about Hobbes about the age of 13. This was very suitable to Mr Hobbes's inclinations, who discharged that trust with great fidelity and diligence. In 1634, he republished his translation of Thucydides, and prefixed to it a dedication to that young nobleman, in which he gives a great character of his father, and represents in the strongest terms the obligations he was under to that illustrious family. The same year he accompanied his noble pupil to Paris, where he applied his vacant hours to the study of natural philosophy, and more especially to the perfect understanding of mechanism, and the causes of animal motion. He had frequent conversations upon these subjects with Father Marin Merfenne; a man deservedly famous, and who kept up a correspondence with almost all the learned in Europe. From Paris he attended his pupil into Italy, where at Pisa he became known to that great astronomer Galileo Galilei, who communicated to him his notions very freely; and after having seen all that was remarkable in that country, he returned with the earl of Devonshire into England. Afterwards, foreseeing the civil wars, he went to seek a retreat at Paris; where, by the good offices of his friend Father Merfenne, he became known to the famous Renatus des Cartes, and afterwards held a correspondence with him upon several mathematical subjects, as appears from the letters of Mr Hobbes published in the works of Des Cartes. But when this philosopher printed afterwards his Meditations, wherein he attempted to establish points of the highest consequence from innate ideas, Mr Hobbes took the liberty of dissenting from him; as did also the French king's mathematical professor, the illustrious Peter Gassendi, with whom Mr Hobbes contracted a very close friendship, which was not interrupted till the death of the former. In 1642, Mr Hobbes printed a few copies of his famous book De Cive, which, in proportion as it became known, raised him many adversaries, who charged him with infilling principles which had a dangerous tendency. Among many illustrious persons who, upon shipwreck of the royal cause, retired to France for safety, was Sir Charles Cavendish, brother to the duke of Newcastle, and this gentleman, being skilled in every branch of the mathematics, proved a constant friend and patron to Mr Hobbes; who, by embarking in 1645 in a controversy about squaring the circle, was grown so famous for it, that in 1647 he was recommended to instruct Charles prince of Wales, afterwards King Charles II. in mathematical learning. His care in the discharge of this office gained him the esteem of that prince in a very high degree; and though he afterwards withdrew his public favour to Mr Hobbes on account of his writings, yet he always retained a sense of the services he had done him; showed him various marks of his favour after he was restored to his dominions; and, as some say, had his picture hanging in his closet. This year also was printed in Holland, by the care of M. Sorbiere, a second and more complete edition of his book De Cive; to which are prefixed two Latin letters to the editor, the one by Mr Gassendi, the other by Father Merfenne, in commendation of it; and in 1650 was published at London a small treatise of Mr Hobbes's, entitled, Human Nature; and another De corpore politico, or "Of the elements of the law."

All this time Mr Hobbes had been digesting with great care and pains his religious, political, and moral principles, into a complete system, which he called the Leviathan, and which was printed in English at London in 1650 and 1651. After the publication of his Leviathan he returned to England, and passed the summer commonly at his patron the earl of Devonshire's seat in Derbyshire, and some of his winters in town, where he had for his intimate friends some of the greatest men of the age. In 1660, upon the restoration, he quitted the country, and came up to London, where he obtained from the king assurance of protection, and had an annual pension of £100, settled upon him out of the privy purse. Yet this did not render him entirely safe: for, in 1666, his Leviathan and his treatise De Cive were censured by parliament; which alarmed him very much, as did also the bringing in of a bill into the house of commons to punish atheism and profaneness. When this storm was a little blown over, he began to think of procuring a beautiful edition of his pieces that were in Latin; but finding this impracticable in England, he caused it to be undertaken abroad, where they were published in quarto in 1668, from the press of John Bleau. In 1669, he was visited by Cosimo de Medicis, then prince, afterwards duke of Tuscany, who gave him ample marks of his esteem and respect; and having received his picture, and a complete collection of his writings, caused them to be repented, the former among his curiosities, the latter in his noble library at Florence. The like visits he received from foreign ambassadors and other strangers of distinction; who were curious to see a person whose singular opinions and numerous writings had made so much noise all over Europe. In 1672, he wrote his own life in Latin verse, when, as he observes, he had completed his 84th year: and, in 1674, he published in English verse four books of Homer's Odyssey; which was so well received, that it encouraged him to undertake the whole Iliad and Odyssey, which he likewise performed and published in 1675. About this time he took his leave of London, and went to spend the remainder of his days in Derbyshire: where, however, he did not remain inactive, notwithstanding his advanced age; but published from time to time several pieces, to be found in the collection of his works. He died in 1679, aged 92.

As to his character and manners, they are thus described by Dr White Kennet, in his Memoirs of the Cavendish family. "The earl of Devonshire (says he) for his whole life entertained Mr Hobbes in his family, as his old tutor rather than as his friend or confident. He let him live under his roof in ease and plenty, and in his own way, without making use of him in any public, or so much as domestic affairs. He would frequently put off the mention of his name, and say, 'He was a humorist, and nobody could account for him.' There is a tradition in the family, of the manners and customs of Mr Hobbes, somewhat observable. His professed rule of health was to dedicate the morning to his exercise, and the afternoon to his studies. And therefore, at his first rising, he walked out, and climbed any hill within his reach; or if the weather was not dry, he fatigued himself within doors by some exercise or other, to be in a sweat; recommending that practice upon this opinion, that an old man had more moisture than heat, and therefore by such Hobby, such motion heat was to be acquired and moisture expelled. After this, he took a comfortable breakfast; and then went round the lodgings to wait upon the earl, the countess, and the children, and any considerable strangers, paying some short addresses to all of them. He kept these rounds till about 12 o'clock, when he had a little dinner provided for him, which he ate always by himself without ceremony. Soon after dinner he retired to his study, and had his candle with 10 or 12 pipes of tobacco laid by him; then shutting his door, he fell to smoking, thinking, and writing for several hours. He retained a friend or two at court, and especially the lord Arlington, to protect him if occasion should require. He used to say, that it was lawful to make use of ill intentions to do ourselves good: 'If I were cast (says he) into a deep pit, and the devil should put down his cloven foot, I would take hold of it to be drawn out by it.' After the restoration, he watched all opportunities to ingratiate himself with the king and his prime ministers; and looked upon his pension to be more valuable, as an earnest of favour and protection, than upon any other account. His future course of life was to be free from danger. He could not endure to be left in an empty house. Whenever the earl removed, he would go along with him, even to his last stage, from Chatsworth to Hardwick. When he was in a very weak condition, he dared not to be left behind, but made his way upon a feather-bed in a coach, though he survived the journey but a few days. He could not bear any discourse of death, and seemed to cast off all thoughts of it. He delighted to reckon upon longer life. 'The winter before he died, he made a warm coat, which he said might last him three years, and then he would have such another. In his last sicknesses frequent questions were, Whether his disease was curable? and when intimations were given, that he might have ease, but no remedy, he used this expression, 'I shall be glad to find a hole to creep out of the world at;' which are reported to have been his last sensible words; and his lying some days following in a silent stupor, did seem owing to his mind more than to his body.'

The reverend Mr Granger observes, that Hobbes's style is incomparably better than that of any other writer in the reign of Charles I. and was for its uncommon strength and purity scarcely equalled in the succeeding reign. "He has in translation (says he) done Thucydides as much justice as he has done injury to Homer; but he looked upon himself as born for much greater things than treading in the steps of his predecessors. He was for striking out new paths in science, government, and religion; and for removing the landmarks of former ages. His ethics have a strong tendency to corrupt our morals, and his politics to destroy that liberty which is the birthright of every human creature. He is commonly represented as a sceptic in religion, and a dogmatist in philosophy; but he was a dogmatist in both. The main principles of his Leviathan are as little founded in moral or evangelical truths, as the rules he has laid down for squaring the circle are in mathematical demonstration. His book on human nature is esteemed the best of his works."