In the 5th century BCE, Zeno of Elea developed a series of
paradoxes designed to show that all is one, and that all
change is illusion. We don't have any of Zeno's writings
surviving from this time, but Aristotle mentions several of
Zeno's paradoxes in books that have come down to us. One of
the most famous is known as The Arrow Paradox.
I'll quote two sources explaining it, but you are welcome to
find others if you'd like.
From Wikipedia:
"In the arrow paradox [...], Zeno states that for motion to
occur, an object must change the position which it occupies.
He gives an example of an arrow in flight. He states that in
any one (duration-less) instant of time, the arrow is neither
moving to where it is, nor to where it is not. It cannot move
to where it is not, because no time elapses for it to move
there; it cannot move to where it is, because it is already
there. In other words, at every instant of time there is no
motion occurring. If everything is motionless at every
instant, and time is entirely composed of instants, then
motion is impossible."
From The
Stanford Encyclopedia of Philosophy: "This argument
against motion explicitly turns on a particular kind of
assumption of plurality: that time is composed of moments (or
‘nows’) and nothing else. Consider an arrow,
apparently in motion, at any instant. First, Zeno assumes that
it travels no distance during that moment—‘it occupies an
equal space’ for the whole instant. But the entire period of
its motion contains only instants, all of which contain an
arrow at rest, and so, Zeno concludes, the arrow cannot be
moving."
Of course we know that motion is possible -- or at
least we will be assuming so for the purposes of Calculus.
Your job is to write a short paper (2-3 pages)
explaining to a friend who is a philosophy major where the
flaw in Zeno's argument is, from a Calculus point of view.
You'll want to frame this in terms of average speed, speed at
an instant, and limits.
If you'd like to include some formulas or more concrete
examples, you may, but the gist of the paper should be
understandable to someone who hasn't had any Calculus. I want
to see how well you can explain the fundamental notion of
instantaneous rate of change without relying on too much
jargon or algebraic computation.
The paper will be due at the beginning of class (3:10 pm) on Monday
2 October. I'm not going to put font size or margin
restrictions on, and I'm not going to obsess over a paper
being slightly under 2 or over 3 pages, so please don't play
font/margin games. The "2-3 page paper" guideline is a way to
communicate that this is not a 1-page quick paper or a more
involved 5-7 page paper.
You do not need to use any outside sources besides the
definition of the paradox quoted above, but you are welcome
to. If you do use anything besides the above or our textbook,
please cite in some appropriate and consistent fashion of your
choosing.
As always, I would encourage you to start early and visit the Writing Center with a draft.