The Stoics were founded by Zeno in around 300 BC. He was a Phoenician born in Cyprus in 360 BC. The philosophy was a combination of Cynicism and Heraclitus, later influenced by Plato’s ideas and abandoned Democritus’ materialism.
The least Greek of any school of philosophy, mainly favoured by Syrians, and later Romans, and nearly all successors to Alexander. Man is the centre of everything.
There is no such thing as chance – everything is determined by natural laws, but it is supervised by a beneficent providence. Logically this precludes human freedom, and man cannot choose to be good or bad, but this did not seem to trouble the Stoics. At first there was only fire, then air, water and earth emerge. Eventually all will return to fire again in an endless cycle.
Everything has a purpose connected with man, animals are good to hunt or eat, and even bed bugs serve to stop man spending too long lying in bed.
Virtue lies within the individual, and cannot be taken away. A man can be tortured and imprisoned, but can retain his virtue. Therefore every man can have perfect freedom if he can emancipate himself from mundane desires. A doctrine of endurance – happy in adversity. Socrates was one of their great heroes – his calmness in face of death, contention that injustice did more harm to the perpetrator than victim, indifference to cold and hunger etc.
A true Stoic regards virtue as an end in itself – it is not to gain anything. However, this is unlikely to generate much enthusiasm, and later Stoics believed in divination and astrology.
But good cannot exist without evil. The Roman period involved suffering of slavery, gladiatorial shows, etc. Stoics believed that natural law meant that all humans were equal, there should be the same law for all, and there should be freedom of speech. These ideas were adopted by Christianity.
Pleasure for itself was despised, but happiness in the form of freedom from passion and disturbance is good. All passions are bad, ie there is no such thing as good passion.
Stoics accepted perception, but acknowledged uncertainty – so that any conclusion could only be probable. However, they believed in innate premises, so that the deductive process could be used. This approach was accepted through the middle ages to Descartes.