8 BIT PHILOSOPHY
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Is change merely an illusion?
In 5th Century BC,
Greek philosopher Parmenides proposed
that the universe was not made of many things,
but rather is a single indivisible substance:
An eternal now that encompasses all time
and all entities.
And if the universe is one,
then all change is impossible.
For the very idea of change suggests
something transforming from one state
to another.
But according to Parmenides,
all states occur simultaneously--
change is impossible.
After receiving heavy criticism
from his contemporaries, Parmenides' student,
Zeno of Elea, came to his defense
by creating a series of paradoxes that seek
to prove that time and change are,
in fact, utter nonsense.
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Consider a situation in which a motorcyclist
races a man on foot.
Let's assume the man is given
a 50 meter head start.
By the time the motorcyclist reaches
the 50 meter mark, the man will have moved
a small distance forward.
And when the motorcyclist catches up
to the ensuing spot, the man will have moved
farther still.
If there are an infinite number
of measurable distances between
any two points, the man will always be
a minute distance ahead of the biker.
This, then, will go on indefinitely,
and the biker will never catch the man.
But this is absurd!
For our perceptions tell us the motorcyclist
would quickly overtake the man.
Therefore, Zeno's paradox tells us
that our perceptions are flawed
and that a change in distance is preposterous.
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In another of his paradoxes, Zeno talks
of an arrow being shot at a target.
If it takes the arrow one second to travel
60 feet, it would take .5 seconds to travel
half that distance.
A quarter second to travel
half that distance, and so on.
If this process continues, we'll have
eventually reach a unit of time during which
the arrow will occupy a space at complete rest.
Let's call this unit of duration this time
"a moment".
If the arrow's trajectory is the sum
of these stationary moments,
then how will the arrow ever reach its target?
And thus motion is nonsensical.
Zeno's paradoxes have challenged scholars,
philosophers, and mathematicians for over
2,500 years.
If nothing else, they force us
to continuously reconsider our reasoning
about the nature of space and time.