AGENDA
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Natural Phil – final
thoughts
Democritus
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 Art Choice – try and decide
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Why is there something rather than nothing?
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These “protoscientists” –
 Curious!
 Wondered about the physical world!
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They posed scientific questions prematurely!
 Mean?
 Hint: (This is why philosophy still matters!)
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Only fragments survived. Mostly known through
Aristotle’s writings about them.
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Nothing can come from nothing. Assumed that something
had always existed.
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Interested in the natural world. Observed nature – they
were philosophers and scientists (one and the same).
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Turned away from religious/mythological explanations of
the world. The world could be understood by man. (Later,
Sophocles would swing the pendulum back to the gods.)
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Noticed that nature was in a constant state of
transformation.
Given this constant change, how to answer these two
basic questions?
The first major question/problem:
1.
What is the basic substance at the root of all
change? What is that one thing from which all
things come and to which all things return?
All the earliest philosophers shared this belief in a
basic substance. The question was, what was it?
They observed nature – science! – to try and find
out.
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First known philosopher
Traveled to Egypt; observed pyramids; crops
Predicted a solar eclipse in 585 B.C.E.
Thought that the source of all things was
water
What did he mean?
Hard to know…Ice/Vapor/Water?
Floods of the Nile  crops growing?
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570-526 B.C.E.
Thought the source of all things was air or
vapor
Familiar with Thales…but thought that water
was simply condensed air.
Condensed even more, water became earth.
Thought fire was rarefied (thin) air
Thus, air was the origin of earth, water, and
fire – air was the source of all natural change
The second major question/problem:
2.
The problem of change
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We perceive with our senses that all things
change, but is that really true?
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c. 540 – 480 B.C.E.
Believed that, in fact, nothing changes
Sensory perceptions lie – give an incorrect,
unreliable picture of the world
A rationalist – he believed that reason is the
primary source of our knowledge of the world
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c. 540 – 480 B.C.E.
Sensory perceptions are reliable
“All things flow”
“Cannot step into the same river twice” –
neither you nor the river will be the same
Believed in a “God” or “logos” (a “universal
reason” guiding everything that happens in
nature, the source of everything)
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c. 490 – 430 B.C.E.
Rejected the idea of a single basic substance
Instead, four elements or “roots”: earth, air, fire, &
water
All things are a mixture of all four elements, in
varying proportions
The four elements combine and separate and
combine again
Also believed in two forces: love (which binds) and
strife (which separates) -- just like modern science
(both elements and natural forces)
Thus, everything changes and nothing changes.
Voila!
Intuitively thought that nature is made up
fundamental “stuff” that makes up
everything.
2. Intuitively thought that nature was
governed by a small number of fundamental
laws which account for all the vast
complexity that we observe in the physical
universe.
This came to be known as the IONIAN
ENCHANTMENT
1.
460-370 BCE
Agreed with Heraclitus: everything in nature "flows" or changes.
But behind everything that flowed there were eternal and
immutable things that did not flow. Democritus called them
"atoms."
 “Atoms” mean:
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Eternal
Immutable
Indivisible
“Barbs” “Hooks”
Soul Atoms
 Round, smooth
 Died/disintegrated – flew different directions
▪ Became part of new formation
▪ No immortal soul
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Why are Legos such a cool toy?
What physical properties are found in Legos?
What could they possibly have to do with The
Natural Philosophers?
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From the beginning philosophy sought for
The order behind the disorder
Thales sipped cheap wine
And in this did divine:
“Why it’s nothing at all but pure water!”