Science: A Way of Knowing & Providing Order to the Universe

• Methods of Science• Explanation in Science• Science and Pseudoscience• The Ordered Universe– Geocentric Universe– Heliocentric Universe– Newton’s Laws and the Founding of Modern

Science

Major Methods of Science

• Observation: descriptions of natural phenomena usually in the search for patterns in nature

• Experiment: manipulation of nature to examine a phenomenon

Deductive Method

• Most typical for natural philosophers following the rediscovery of Aristotle by western Europe

• Explanatory method of Plato and Pythagoras

• Clearly expounded by René Descartes in 1637 [Discours de la méthode (Discourse on the Method)].

René Descartes 1596-1650

Inductive or Empirical Method

• Based on observation• The experimental

method is a subset of the inductive method

• Francis Bacon proposed the Great Instauration

• Novum Organum (1620)

Francis Bacon 1561-1626

Human reason can be decieved in the following ways:

• Idylls of the Tribe (incorrect inference of cause and effect)

• Idylls of the Den (one’s views are influenced by others and may be upheld by ignoring contravening evidence)

• Idylls of the Marketplace (false arguments can be convincing due to ambiguity of communication)

• Idylls of the Theater (theories about the world can be false)

William Gilbert• Contemporary of Bacon• Did not recognize Bacon as a

natural philosopher• Bacon critical of Gilbert’s

explanations– The Alchemists have made a

philosophy out of a few experiments of the furnace and Gilbert our countryman hath made a philosophy out of observations of the lodestone.

– [Gilbert] has himself become a magnet; that is, he has ascribed too many things to that force and built a ship out of a shell.

William Gilbert 1544-1603

Explanation

• Hypothesis• Theory• Principle• Law

Attributes of Pseudoscience

• Anything is possible (cannot be falsified)• Vague, exaggerated, untested claims• Refutation of alternative theory, but no

material confirmation of the claim

biology - geology

chemistry physics

mathematics

COM

PLEX

ITY

The Ordered Universe

Construction of Stonehenge• Earthen banks (~3100 BCE)• Wooden Building (~3000 BCE)• Bluestones (~2600 BCE)• Sarsen Stones (2600-2400 BCE)• Final arrangement (2280-1600 BCE)

Aristotle of Stagira 348-322 BCEEudoxus of Cnidus 408-355 BCE

Claudius Ptolemy ~90-168 CE

Nicolaus Copernicus

1473-1543

Giordano Bruno• Dominican and

non-trinitarian• Praised Copernican

system• On trial and

burned at the stake for heresy of Arianism

(1548-1600)

Tycho Brahe and Johannes Kepler

1546-1601 1571-1630

Kepler’s Laws of Planetary Motion• Law of Ellipses

• Equal Area Law

• (Period)2 /(Major Axis)3 is the same for all planets.

Galileo Galilei

• Direct observations of the heavens with his improved telescope

• Saw blemishes on the moon and (later) on the sun

• Recorded the Medician stars and explained their changing positions as moons circling Jupiter

1564-1642

Isaac Newton

• Law of Gravity: the strength of the gravitational force between two bodies of mass is relative to the inverse square of the distance between their centers of mass.

• Used this concept of gravity to explain Kepler’s Laws of motion.

1642-1727

Robert Hooke, Edmond Halley, John Flamsteed

Robert Hooke 1635-1703 Edmond Halley 1656-1742 John Flamsteed 1646-1719

Newton’s Laws of Motion

• Conservation of momentum (P=mv)

• ƩP=0