Knowing Why Things Work
Edwin Hutchins, Cognition_in_the_Wild
The Mercator
-projection chart is a specialized analog computer , and the properties of the
chart that make its use possible are profoundly mathematical in nature . But
those parts of the computation were
performed by cartographers and need not be a direct concern of the chart 's
users.
The
cartographer has already done part of the computation for every navigator who
uses his chart . The computation has been distributed over time as well as
across social space. The navigator
doesn't have to know how the chart was made and doesn't need to know about the
properties of the Mercator projection that give special computational meaning
to straight lines.
The device
is actually more powerful if the user does not have to know how or why it
works, because it is thereby available to a much larger community of users. The
computational abilities of the mind of the navigator penetrate only the
shallows of the computational problems of navigation.
In the
day-to-day practice of navigation, the deeper problems are either transformed
by some representational artifice into shallow ones or not addressed at all.
“Even today,
of course, since the ultimate sources of time –keeping and position -finding
are the heavenly bodies.! the sailor must look up at the sky.”
But so long and so far has the chain of
experts professional astronomers , mathematicians , almanac -makers, instrument
-makers and so forth - separated the ordinary man from the first -hand
observation that he has ceased to think beyond the actual clock , time -signal
, map calendar , or whatever it may be that " tells " him what he
wishes to know .”
(Taylor 1971) Frake (1985: 268) makes a
similar point about modern knowledge of the tides :
“[ Modern
tidal theory] is far beyond the reach of the modern navigator. Sailors today have no need to understand tidal
theory at any level . They merely consult their tide tables anew for each voyage.”
