Philosopher, Statesman, & Orator

Marcus Tullius Cicero

Cicero, who died on this day in 43 BC, was a Roman philosopher, statesman, lawyer, orator, political theorist, consul and constitutionalist. He came from a wealthy municipal family of the equestrian order, and is widely considered one of Rome's greatest orators and prose stylists.
His influence on the Latin language was so immense that the subsequent history of prose in not only Latin but European languages up to the 19th century was said to be either a reaction against or a return to his style.   According to Michael Grant, "the influence of Cicero upon the history of European literature and ideas greatly exceeds that of any other prose writer in any language."  Cicero introduced the Romans to the chief schools of Greek philosophy and created a Latin philosophical vocabulary (with neologisms such as humanitas, qualitas, quantitas, and essentia)  distinguishing himself as a linguist, translator, and philosopher.
Petrarch's rediscovery of Cicero's letters is often credited for initiating the 14th-century Renaissance.  According to Polish historian Tadeusz Zieliński, "Renaissance was above all things a revival of Cicero, and only after him and through him of the rest of Classical antiquity."  The peak of Cicero's authority and prestige came during the eighteenth-century Enlightenment,  and his impact on leading Enlightenment thinkers such as John Locke, David Hume, and Montesquieu was substantial.  His works rank among the most influential in European culture, and today still constitute one of the most important bodies of primary material for the writing and revision of Roman history, especially the last days of the Roman Republic.  
Though he was an accomplished orator and successful lawyer, Cicero believed his political career was his most important achievement. It was during his consulship that the Catiline conspiracy attempted the government overthrow through an attack on the city from outside forces, and Cicero suppressed the revolt by executing five conspirators without due process. During the chaotic latter half of the 1st century BC marked by civil wars and the dictatorship of Gaius Julius Caesar, Cicero championed a return to the traditional republican government. Following Julius Caesar's death Cicero became an enemy of Mark Antony in the ensuing power struggle, attacking him in a series of speeches. He was proscribed as an enemy of the state by the Second Triumvirate and subsequently murdered in 43 BC.
His works are still read today by both lovers of the classics and language in general.  Here are some representative quotations from Cicero:

“As for myself, I can only exhort you to look on Friendship as the most valuable of all human possessions, no other being equally suited to the moral nature of man, or so applicable to every state and circumstance, whether of prosperity or adversity, in which he can possibly be placed. But at the same time I lay it down as a fundamental axiom that "true Friendship can only subsist between those who are animated by the strictest principles of honour and virtue." When I say this, I would not be thought to adopt the sentiments of those speculative moralists who pretend that no man can justly be deemed virtuous who is not arrived at that state of absolute perfection which constitutes, according to their ideas, the character of genuine wisdom. This opinion may appear true, perhaps, in theory, but is altogether inapplicable to any useful purpose of society, as it supposes a degree of virtue to which no mortal was ever capable of rising.”  ― Marcus Tullius Cicero

“Neither can embellishments of language be found without arrangement and expression of thoughts, nor can thoughts be made to shine without the light of language. ”  ― Marcus Tullius Cicero

“Let us assume that entertainment is the sole end of reading; even so I think you would hold that no mental employment is so broadening to the sympathies or so enlightening to the understanding. Other pursuits belong not to all times, all ages, all conditions; but this gives stimulus to our youth and diversion to our old age; this adds a charm to success, and offers a haven of consolation to failure. Through the night-watches, on all our journeyings, and in our hours of ease, it is our unfailing companion.”  ― Marcus Tullius Cicero

“Everyone has the obligation to ponder well his own specific traits of character. He must also regulate them adequately and not wonder whether someone else's traits might suit him better. The more definitely his own a man's character is, the better it fits him.”  ― Marcus Tullius Cicero