Philosophy 160
Spring 2004
Observation and Meaning
Here are some claims:
A. Water is H2O.
B. Water and ice are the same stuff.
C. Water freezes at 0 ˚C and 1 atm pressure.
D. Water will melt the Wicked Witch of the West. (Fortunately, we
now have her in captivity.)
E. Water is not a good conductor of electricty.
Which of these claims would you say are synthetic? Which are analytic?
Why are you inclined to classify them this way? (Here's what I'd say about them.)
Now let’s do a thought experiment.
It’s the year 1600 and we are intrepid scientists. We also have an
interplanetary transporter.
We have discovered a planet very much like ours called Twin Earth.
We go there and discover that the rivers, lakes, streams, and aqueducts are
filled with a liquid that the Twin Earthlings drink, cook with, bathe in,
swim in, etc. We take a sample back to our laboratory.
Question: Is this stuff water? (How do we decide?)
(Remember that in 1600, not only are we without fancy equipment to make
an elemental analysis of this stuff, but we don’t have a concept of “element”
beyond the earth-air-fire-water framework.)
The thought experiment continues:
The intrepid scientists in 1600 had the foresight to stash some samples
of the liquid from Twin Earth. It’s now 1785. You’re a scientist,
working in the laboratory of Lavoisier, the discoverer of oxygen. Your
task in to determine the elemental composition of water. You take a
sample of the stuff in the Seine. You find that you can change that
liquid (by way of an electrolysis set-up) to two volumes of hydrogen gas and
one volume of oxygen gas. Next, you take one of the samples of liquid
recovered from Twin Earth. Electrolysis of that liquid yields a different
elemental composition (call it XYZ).
Question: Is the stuff from Twin Earth water? Why or why
not?
A slightly different version of events:
The intrepid scientists in 1600 had the foresight to stash some samples
of the liquid from Twin Earth. It’s now 1785. You’re a scientist,
working in the laboratory of Lavoisier, the discoverer of oxygen. Your
task in to determine the elemental composition of water. You take a
sample of the stuff in the Seine. You find that you can change that
liquid (by way of an electrolysis set-up) to two volumes of hydrogen gas and
one volume of oxygen gas.
Due to poor lab-keeping, however, the reserved sample of liquid from Twin
Earth can’t be found in 1785. Instead, it’s rediscovered in 2004.
Elemental analysis of this liquid yields a different elemental composition
(call it XYZ).
Questions: What assumptions about the stuff from Twin Earth would
you have been inclined to make in 1785 based on the available data? With
the additional data in 2004, how would you want to explain (or revise) those
earlier assumptions?
A shocking discovery! In 2004, it is discovered that the
water in certain lakes, rivers, and streams in the Southern Hemisphere has
an elemental composition of XYZ. (No one bothered to check before.)
In all other respects, this stuff behaves just like the rest of Earth water
(and like that stuff from Twin Earth).
Question: Is XYZ water? Why or why not?
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