The 17th century was a time of incredibly rapid change and a
great
deal of uncertainty.
Everything taken for granted in earlier times had changed, was
changing,
or was about to change. It's uncomfortable to live in such
times.
We want certainty! One playwright (Maurice Maeterlink I think)
has a
line about such uncertainty, "Not to know where one is, where one
has been, not to know where one is going: I would rather not
live." Not surprisingly, the great thinkers of the 17th century
turned their minds to
task of providing certainty, trying to show how one could know that
certain
things were true. Foremost among them: Bacon, Descartes, and
Pascal.
These men did an excellent job in suggesting ways one might effectively
pursue truth and certainty, and each of them did quite a bit to provide
order and
assurance amid the uncertainties of the 17th century.
SOURCES OF KNOWLEDGE
When we claim we "know" something, what are the possible
sources
of that knowledge? Here are some possibilities:
--Authority
(we get our knowledge from an expert)
--Experience (we get our knowledge from things we personally see,
taste, touch, smell)
--Reason
(we get our knowledge through logic)
--Revelation
(we get out knowlege from some transcendent source)
--Innate (we are born with knowlege)
Which of these is most important? Most of the time, we
resort
to authority. If we want to know the speed of light (299,792.458
kilometers per second), we want to just look in a textbook: we don't
want to replicate the Michelson-Morley experiements ourselves!
But relying on authority wasn't sufficient in the 17th century.
Why? In just about every area, whether in astronomy, physics,
medicine or religion, the authorities simply did not agree. Who
was the "authority" in each of these areas?
2. The Idols of the Den or Cave. Our own previous
experiences tend to color our understanding and sometimes mislead
us. We must
get
rid of such prejudices and be willing to challenge our old ideas if we
are to arrive at truth.
3. The Idols of the Marketplace. Our search for truth can be made harder by confusion in the way we exchange our ideas. The exchange of ideas with others may lead to circulation of false ideas. In particular, have to watch out for the medium of exchange, words.
4. The Idols of the Theater. Just as actors can make pretense seem reality, so our "great" thinkers can make false or inaccurate concepts seem like reality. The great philosophic systems in particular (like the medieval synthesis of knowledge I talked about) especially create an illusion of knowlege by giving us a majetic spectacle. Such systems may make false ideas extremely attractive to us and hard to challenge.What do all hot objects have in common? Movement of some
sort--and Bacon concludes that heat is essentially movement: the
right answer!
Note that such systematic treatment eventually does produce
not
merely a plausible answer, but an answer one can have considerable
confidence
in.
Bacon predicted that such systematic examination of nature would
greatly
increase knowledge and make lives better, and, as Bacon's method has
been applied through the years, it has done what he thought it
would. It has led to a better understanding of physics, biology,
geology, etc.