Although there is no excuse for promoting pseudo-scientific ideas today, I find it difficult to condemn
ancient and
medieval practitioners of pseudosciences such as
Although astrologers, alchemists, and numerologists were on an
a priori search for
magical properties of the stars, planets, numbers, or what have you, many proceeded with meticulous care, a foreshadowing of the
scientific method. Although the theoretical basis to arrive at correct answers did not yet exist, these people made many collateral discoveries which helped start the scientific revolution.
Nicolaus Copernicus,
Tycho Brahe, and
Johannes Kepler earned their respective livings mostly from casting
horoscopes for the nobility of Europe. Although Kepler's construct of nested
polyhedra and spheres determining the orbits of the
planets as well as the
music of the spheres would be considered silly today, it was a valid (
heliocentric!)
cosmological model that fit with the observations of the day.
The seminal book on
mining techniques and
metallurgy,
De re metallica, was written by
Saxon alchemist
Georgius Agricola. And the first
1 chemical element not known to the ancients,
phosphorus, was discovered by another German alchemist,
Hennig Brandt, around
1669.
Numerologists such as
Pythagoras and
Leonardo of Pisa, aka
Fibonacci, assigned mystical properties to numbers and mathematical objects. This did not prevent them from making valid mathematical discoveries that we use to this day.
As I said at the beginning, promoting pseudoscience is inexcusable today, but we must be careful what we label "pseudoscience".
Some of the techniques of
chiropractic and
acupuncture2 appear to work, even though they have no sound medical basis. These latter areas are more
ad hoc and results-based, and do not deserve condemnation unless their proponents label them as "
science".
1This may not be entirely accurate.
De re metallica mentions
bismuth, although Agricola did not recognize it as an element.
2I will leave it to better-qualified people to explain any true scientific results from the study of
chi.