The philosophical thought of the Roman Emperor Marcus Aurelius represents the reflection of the last great exponent of the Stoic doctrine, belonging to the so-called new Stoa or "Roman Stoicism".

His philosophy retraces the Stoic attitude, starting from the withdrawal into oneself, aided by political activism, following the Fate. The celebration of interiority is clearly evident from the title of his only written work, the Meditations, also known as Thoughts, Memoirs, or To Himself.

Marcus Aurelius wrote the twelve books that make up the work between 170 and 180, during breaks from his numerous travels, in Greek of the koinè, as an exercise for his own guidance and self-improvement, influenced by some of his youth teachers who had pushed him towards philosophy; among them Quintus Junius Rusticus, Diognetus, Claudius Maximus, and Apollonius of Chalcedon, remembered in Book I. The literary style is inspired by that of the grammarian Alexander of Cotiaeum, another of his tutors, as Marcus himself recalls. The title of this work was a posthumous addition; originally, Marcus titled the work To Himself, but it is not known if he intended to make it public. The Thoughts demonstrate a logical mind, and his notes are representative of Stoic philosophy and its spirituality, also offering a fine and detailed psychological portrait. The book is considered one of the literary and philosophical masterpieces of all time.

Marcus Aurelius's education took place at home: in line with the aristocratic trends of the time, his great-grandfather Severus encouraged him to avoid public schools. One of his teachers, Diognetus, proved particularly influential, introducing Marcus to a philosophical view of life and teaching him rationality. In April 132, at the behest of Diognetus (identified by some as the recipient of the letter Epistle to Diognetus), Marcus began to wear the clothes and adopt the habits typical of philosophers: while studying, he wore a rough Greek cloak, and he slept on the ground until his mother convinced him to sleep on a bed.

A new series of preceptors, the grammarian Alexander of Cotiaeum, Trosius Aper, and Tuticius Proculus continued to take care of his education in 132–133. Little is known about these last two teachers (both of Latin), while Alexander is described as an important literary figure of his time. Marcus thanks Alexander for his training in literary style, evident in many passages of the Meditations.

After donning the toga virilis in 136, he probably began his oratorical training. He had three Greek teachers, Aninus Macer, Caninius Celer, and Herodes Atticus, and one Latin teacher, Marcus Cornelius Fronto, whom Marcus often remembers as his teacher of style and life in the Meditations. Fronto and Atticus, however, became his tutors only after his adoption by Antoninus in 138. The preponderance of Greek tutors indicates the importance of the language for the Roman aristocracy. This was the age of the Second Sophistic, a revival of Greek literature. Although educated in Rome, Marcus would write part of the Meditations in Greek.

Fronto was considered, as an orator, second only to Cicero, or on par with the "glory of Roman eloquence", a fame that today, based on the few remaining fragments, may leave one astonished. He had no sympathy for Herodes, although Marcus eventually managed to establish good relations between them. Fronto had complete mastery of Latin and, skilled in word choice, was capable of formulating unusual expressions through literary art. A significant amount of correspondence between Fronto and Marcus has survived to us. The two were very close; Marcus called him "my dear Fronto" and "my joy" and also spent a lot of time with his wife and daughter, both named Cratia, in casual conversations.

On the occasion of the imperial ascent of his pupils, Marcus and Lucius Verus, Fronto left his home in Cirta and on 28 March returned to his Roman residence. He sent a note to the imperial freedman Charilas, asking to be able to contact the emperors because, he said later, he had not dared to write directly to the emperors. The teacher showed immense pride in his pupils: reflecting on the speech given for the ascent to the consulship in 143, where he praised the young Marcus, Fronto was enthusiastic: "There was then an extraordinary natural ability in you, now perfected into excellence; the growing grain is now a ripe harvest".