This document summarizes several ancient Greek philosophers and their ideas, including Socrates, Plato, Aristotle, and Democritus. Socrates helped lay the foundations of western philosophy through his use of inductive reasoning and belief that wrongdoing stems from ignorance. Plato was a student of Socrates and documented his teachings, founding the Academy in Athens. Aristotle studied under Plato and made contributions across many fields, including physics, biology, and optics. Democritus originated the atomic theory that the universe is composed of indivisible atoms and void.

1. the athenian
dichoso, eunice
lucido, mavic

2. After the subjugation of Ionian and
destruction of Miletus by the Persian
Athens commanded leadership of Greek
science.
The following are the famous Ancient
Greek philosophers of this period and their
beliefs.

3. Socrates (470-399 BC)
Socrates was a gifted thinker of
ancient Athens who helped lay the
foundation of western philosophy.
The methods he used and the
concepts he proposed, along with his
courageous defense of his ideas
against his enemies, profoundly
influenced the philosophical and
moral tenor of western thought over
the centuries.
He was imprisoned and was found guilty of promoting dangerous
ideas. He was sentenced to death and was made to drink hemlock
– a poison considered as capital punishment in ancient Athens.

4. Socrates’ contributions
• The unexamined life is not worth living. In other words, a
human being must not be complacent and self-satisfied;
instead, he must be ever probing, exploring, and
reconnoitering his soul in order to discover ways to improve.
• Pioneered the use of inductive reasoning to draw logical
conclusions. According to Aristotle, Socrates founded the
"scientific method."
• Demonstrated that wrongdoing results from ignorance. If a
man lies, Socrates might have said, he does so because he
does not understand the benefits of telling the truth.

5. Socrates’ contributions
• Inspired philosophers in his own time and in later times to
pursue the truth through rigorous analysis of available, facts,
opinions, and so on.
• Showed the world the meaning of integrity and moral
commitment by accepting a death sentence rather than
retracting his principles.
• Made clear that a human being is more than his appearance.
Socrates was ugly, wore old clothes, and walked barefooted
through the streets of Athens. But his mind and the words he
spoke were beautiful.

6. Plato (427-347 BC)
Plato was one of the most famous
Athenian philosophers and a pupil of
Socrates; it is only through Plato’s
writings that we know the thoughts
and ideas of Socrates. He served in
the army and fought in the
Peloponnesian War against Sparta.
Afterwards, before he met Socrates,
he received an education in
grammar, music, gymnastics and
above all, philosophy. Later in life, he
enjoyed accompanying Socrates in
excursions to the city's public places
to lead discussions with randomly
met people.

7. Plato
When Socrates was executed in 399
B.C., Plato decided to write down his
master’s philosophical beliefs. He
travelled around the Mediterranean,
visiting Italy and Egypt. Upon his return
to Athens in 388 B.C., he founded his
own Academy. Plato's most significant
ideas on power hierarchy and the state
are represented in such works as ‘The
Republic’ and ‘Laws’. In his ‘Theory of
Forms’, Plato formulated his solution to
the problem of universals.

8. Plato’s contributions
• Plato often discusses the father-son relationship and the
"question" of whether a father's interest in his sons has much to
do with how well his sons turn out.
• “The wise person who accepts the power thrust upon him by the
people who are wise enough to choose a good master. ”
• Celestial bodies are divine and noble and their motions are
uniform and circular around the earth.
• The universe is perfect sphere.
• The real world is the “world of Forms” beyond human senses
and can be understood only by using logic and not by
observations and experiments. That the objects that we see,
according to Plato, are not real, but literally mimic the real
Forms.

9. Aristotle (384-322 BC)
Full name:
Aristoteles
Born:
384 BC
Stageira, Chalcidice
Died:
322 BC (age 61 or 62)
Religion:
Western philosophy

10. Aristotle
Aristotle (Greek: Ἀριςτοτελης,
Aristotélēs) (384 BC – 322 BC) was
a Greek philosopher, a student of
Plato and teacher of Alexander
the Great.
His writings cover many subjects,
including physics, metaphysics,
poetry, theater, music, logic,
rhetoric, politics, government,
ethics, biology, and zoology.

11. Aristotle in Biology and Medicine
• Ancient greek philosopher and botanist.
• Torpedo fuscomaculata & Leopard shark

12. Aristotle in Physics
• The five elements
–
–
–
–
–
Fire which is hot and dry.
Earth which is cold and dry.
Air
which is hot and wet.
Water which is cold and wet.
Aether which is the divine substance that makes up the
heavenly spheres and heavenly bodies (stars and
planets).

13. Aristotle in Optics
Aristotle held more accurate theories on some optical
concepts than other philosophers of his day. The earliest known
written evidence of a camera obscura can be found in Aristotle's
documentation of such a device in 350 BC in Problemata.
Aristotle's apparatus contained a dark chamber that had a
single small hole, or aperture, to allow for sunlight to enter.
Aristotle used the device to make observations of the sun and
noted that no matter what shape the hole was, the sun would
still be correctly displayed as a round object. In modern cameras,
this is analogous to the diaphragm.
Aristotle also made the observation that when the distance
between the aperture and the surface with the image increased,
the image was magnified

14. The spheres of Eudoxus
explain the motions in the
heavens by means of nested
spheres rotating about
various axes at different
rates. The earth is located at
the center. (Eudoxus used 27
spheres; Aristotle used 56)
The Pythagoreans set astronomy on a quantitative path,
The Pythagoreans set astronomy on a quantitative path,
and coincidentally imagined a cosmos which was not
and coincidentally imagined a cosmos which was not
geocentric, with a "central fire" around which the earth,
geocentric, with a "central fire" around which the earth,
counter-earth, sun, moon, planets, and stars revolved. It
counter-earth, sun, moon, planets, and stars revolved. It
should also be noted that a truly heliocentric model was
should also be noted that a truly heliocentric model was
proposed by Aristarchus of Samos,
proposed by Aristarchus of Samos,

15. The Lyceum

16. Aristotle and the Lyceum
Aristotle came back to Athens in 335 B.C., and spent
the next 12 years running his own version of an
academy, which was called the Lyceum, named after
the place in Athens where it was located, an
old temple of Apollo.
Aristotle’s preferred mode of operation was to spend a
lot of time walking around talking with his
colleagues, then write down his arguments. The
Aristotelians are often called the Peripatetics:
people who walk around.

17. The Aristotelian Tradition
Plato and Aristotle brought rational inquiry into the
sciences, and in to new levels. Although their approaches
were quite different, both advocated systematic and rational
investigation.
Plato taught that the world around us is one of illusion that the senses could be easily deceived - and so the truth
could best be discovered by applying logic and reasoning.
Aristotle, in contrast, advocated searching for the truth by
first observing, and then constructing models which could
explain the observations.

18. Leucippus & Democritus
With the work of Leucippus
and Democritus ancient Greek
philosophy reaches its zenith
when the initial question of
Thales after the true nature of
matter culminated 180 years
later in the subtle concept of
atoms, which bears an amazing
resemblance to the 20th century's
view of chemistry.

19. Leucippus & Democritus
For this reason, Leucippus and
Democritus have undoubtedly
deserved the first price for the
best guess in antiquity, as far as
natural science is concerned.
Unfortunately their
contemporaries did not share
their views with the same
enthusiasm.

20. Leucippus & Democritus
They held that the nature of
things consists of an infinite
number of extremely small
particles, which they called
atoms. Atoms are
physically, but not
geometrically, indivisible.

21. Democritus
(460 - 370 BC)
Promulgated the atomic
theory, which asserted that the
universe is composed of two
elements: the atoms and the
void in which they exist and
move.
He illustrated the movement
of atoms with an observation he
made in nature

22. Leucippus (480 - about 420 BC)
A Greek philosopher who
originated the atomic theory of
indivisibles developed later by
Democritus.
World is composed of atoms
which are unchangeable,
incorruptible, imuutable but
collide move and combine.

23. Questions?

24. Thank you.