Editing Pre-Socratic philosophy (section)

==Topics==
===Knowledge===
The ''mythologoi'', Homer and Hesiod, along with other poets, centuries before the pre-Socratics, thought that true knowledge was exclusive to the divine. But starting with Xenophanes, the pre-Socratics moved towards a more natural approach to knowledge.{{sfn|Lesher|2008|pp=458-459}} The pre-Socratics sought a method to understand the cosmos, while being aware that there is a limit to human knowledge.{{sfn|Lesher|2008|p=476}}

While Pythagoras and Empedocles linked their self-proclaimed wisdom to their divinely inspired status, they tried to teach or urge mortals to seek the truth about the natural realm—Pythagoras by means of mathematics and geometry and Empedocles by exposure to experiences.{{sfn|Lesher|2008|pp=466-468}} Xenophanes thought that human knowledge was merely an opinion that cannot be validated or proven to be true. According to Jonathan Warren, Xenophanes set the outline of the nature of knowledge.{{sfn|Warren|2014|pp=51}} Later, Heraclitus and Parmenides stressed the capability of humans to understand how things stand in nature through direct observation, inquiry, and reflection.{{sfn|Lesher|2008|p=476}}

=== Theology ===
Pre-Socratic thought contributed to the demythologization of the Greek popular religion. The narrative of their thought contributed to shifting the course of ancient Greek philosophy and religion away from the realm of divinity and even paved the way for teleological explanations.{{sfn|Robinson|2008|pp=496-497}} They attacked the traditional representations of gods that Homer and Hesiod had established and put Greek popular religion under scrutiny, initiating the schism between natural philosophy and theology.{{sfn|Robinson|2008|p=497}} Pre-Socratic philosophers did not have atheistic beliefs, but it should be kept in mind that being an atheist those days was not without social or legal dangers. Despite that, arguments rejecting deities were not barred from the public sphere which can be seen in Protagoras's quotation on the gods: "About the gods I am able to know neither that they exist nor that they do not exist."{{sfn|Sedley|2013|p=140}}

The theological thought starts with the Milesian philosophers. It is evident in Anaximander's idea of the ''[[Apeiron (cosmology)|apeiron]]'' steering everything, which had other abilities usually attributed to Zeus.{{sfn|Robinson|2008|pp=485-487}} Later, Xenophanes developed a critique of the anthropomorphism of the gods. Xenophanes set three preconditions for God: he had to be all good, immortal and not resembling humans in appearance, which had a major impact on western religious thought.{{sfn|Robinson|2008|pp=487-488}}

The theological thought of Heraclitus and Parmenides is not entirely certain, but it is generally accepted that they believed in some kind of divinity. The Pythagoreans and Empedocles believed in the [[Reincarnation|transmigration of souls]]. Anaxagoras asserted that cosmic intelligence (''[[nous]]'') gives life to things. Diogenes of Appollonia expanded this line of thinking and might have constructed the first teleological argument "it would not be possible without Intellection for it so to be divided up that it has the measures of all things — of winter and summer and night and day and rains and winds and fair weather. The other things, too, if one wishes to consider them, one would find disposed of in the best possible way."{{sfn|Robinson|2008|pp=490-492}} While some pre-Socratics were trying to find alternatives to divinity, others were setting the foundation of explaining the universe in terms of teleology and intelligent design by a divine force.{{sfn|Robinson|2008|p=496}}

===Medicine===
Prior to the pre-Socratics, health and illness were thought to be governed by gods.{{sfn|Longrigg|1989|p=1-2}} Pre-Socratic philosophy and medicine advanced in parallel, with medicine as a part of philosophy and vice versa.{{sfn|Van der Eijk|2008|p=385}} It was [[Hippocrates]] (often hailed as the father of medicine) who separated – but not completely – the two domains.{{sfn|Van der Eijk|2008|pp=385-386}} Physicians incorporated pre-Socratic philosophical ideas about the nature of the world in their theoretical framework, blurring the border between the two domains. An example is the study of epilepsy, which in popular religion was thought to be a divine intervention to human life, but Hippocrates' school attributed it to nature, just as Milesian rationalism demythologized other natural phenomena such as earthquakes.{{sfnm|1a1=Van der Eijk|1y=2008|1p=387|2a1=Longrigg|2y=2013|2pp=1-2}} The systematic study of anatomy, physiology, and illnesses led to the discovery of cause-effect relations and a more sophisticated terminology and understanding of the diseases that ultimately yielded rational science.{{sfnm|1a1=Van der Eijk|1y=2008|1pp=387, 395-399|2a1=Longrigg|2y=2013|2pp=1-2}}

===Cosmology===
The pre-Socratics were the first to attempt to provide reductive explanations for a plethora of natural phenomena.{{sfn|Wright|2008|p=414}}

Firstly, they were preoccupied with the mystery of the cosmic matter—what was the basic substance of the universe? Anaximander suggested ''apeiron'' (limitless), which hints, as Aristotle analyzed, there is no beginning and no end to it, both chronologically and within the space.{{sfn|Wright|2008|p=415}} Anaximenes placed ''aêr'' (air) as the primary principle, probably after realizing the importance of air to life and/or the need to explain various observable changes.{{sfn|Wright|2008|p=416}} Heraclitus, also seeking to address the issue of the ever changing world, placed fire as the primary principle of the universe, that transforms to water and earth to produce the universe. Ever-transforming nature is summarized by Heraclitus' axiom ''panta rhei'' (everything is in a state of flux).{{sfn|Wright|2008|pp=416-417}} Parmenides suggested two ever-lasting primary building blocs, night and day, which together form the universe.{{sfn|Wright|2008|p=417}} Empedocles increased the building blocks to four and named them roots, while also adding Love and Strife, to serve as the driving force for the roots to mingle.{{sfn|Wright|2008|p=418}} Anaxagoras extended even more the plurality of Empedocles, claiming everything is in everything, myriads of substances were mixing among each other except one, ''Nous'' (mind) that orchestrates everything—but did not attribute divine characteristics to ''Nous''.{{sfn|Wright|2008|p=419 & 425}} Leucippus and Democritus asserted the universe consists of atoms and void, while the motion of atoms is responsible for the changes we observe.{{sfn|Wright|2008|pp=419-420}}

=== Rationalism, observation and the beginning of scientific thought ===

The pre-Socratic intellectual revolution is widely considered to have been the first step towards liberation of the human mind from the mythical world and initiated a march towards reason and scientific thought that yielded modern western philosophy and science.{{sfnm|1a1=Barnes|1y=1987|1p=17|2a1=Hankinson|2y=2008|2pp=453-455}} The pre-Socratics sought to understand the various aspects of nature by means of rationalism, observations, and offering explanations that could be deemed as scientific, giving birth to what became Western rationalism.{{sfnm|1a1=Barnes|1y=1987|1p=16|2a1= Laks|2a2=Most|2y=2018|2p=36}} Thales was the first to seek for a unitary arche of the world. Whether arche meant the beginning, the origin, the main principle or the basic element is unclear, but was the first attempt to reduce the explanations of the universe to a single cause, based on reason and not guided by any sort of divinity.{{sfn|Hankinson|2008|pp=435-437}} Anaximander offered the [[principle of sufficient reason]],{{sfn|Hankinson|2008|pp=445}} a revolutionary argument that would also yield the principle that nothing comes out of nothing.{{sfn|Hankinson|2008|pp=446}} Most of pre-Socratics seemed indifferent to the concept of teleology, especially the Atomists who fiercely rejected the idea.{{sfn|Hankinson|2008|pp=449}} According to them, the various phenomena were the consequence of the motion of atoms without any purpose.{{sfn|Hankinson|2008|pp=449-450}} Xenophanes also advanced a critique of anthropomorphic religion by highlighting in a rational way the inconsistency of depictions of the gods in Greek popular religion.{{sfn|Hankinson|2008|p=453}}

Undoubtedly, pre-Socratics paved the way towards science, but whether what they did could constitute science is a matter of debate.{{sfn|Taub|2020|pp=7-9}} Thales had offered the first account of a reduction and a generalization, a significant milestone towards scientific thought. Other pre-Socratics also sought to answer the question of arche, offering various answers, but the first step towards scientific thought was already taken.{{sfn|Hankinson|2008|pp=435-437}} Philosopher [[Karl Popper]], in his seminal work ''Back to Presocratics'' (1958) traces the roots of modern science (and the West) to the early Greek philosophers. He writes: "There can be little doubt that the Greek tradition of philosophical criticism had its main source in Ionia&nbsp;... It thus leads the tradition which created the rational or scientific attitude, and with it our Western civilization, the only civilization, which is based upon science (though, of course, not upon science alone)." Elsewhere in the same study Popper diminishes the significance of the label they should carry as purely semantics. "There is the most perfect possible continuity of thought between [the Presocratics'] theories and the later developments in physics. Whether they are called philosophers, or pre-scientists, or scientists, matters very little."{{sfn|Vamvacas|2009|pp=19,23}} Other scholars did not share the same view. F. M. Cornford considered the Ionanians as dogmatic speculators, due to their lack of empiricism.{{sfn|Curd|2008|p=18-19}}