What are the differences between realism and idealism?

Foundation of psychology
Chapter 9
What is science?

Science’s claim of superiority was based on four principles

• Realism:
  There is a physical world with independent objects, which can be understood by human intellect
• Objectivity:
  Knowledge of the physical world does not depend on the observer.
  ‘Objective’ agreement among people is possible, irrespective of their worldviews.
  • Science aims to uncover this knowledge so that it becomes public, verifiable and useable
• Truth
  Scientific statements are true when they correspond to the physical reality
• Rationality
  Truth is guaranteed because scientific statements are based on sound method.

Thoughts about information acquisition from Ancient Greece to the end of the nineteenth century

Thoughts before the scientific revolution

Plato, Aristotle and the sceptics

Plato
A strong rationalist view of knowledge acquisition.
Human perception was fallible and the observable world was only a shadow of the Real world.
The human soul had innate knowledge of the universe, which could be harnessed

Aristotle
More scope for observation and made a distinction between deductive reasoning and inductive reasoning.
True, theoretical knowledge started from axioms, form which new knowledge was deduced via so-called demonstrations.
Perception was the source of information but not knowledge itself.
Correspondence theory of truth: a statement is true when it corresponds with reality. Assumes that there is a physical reality which has priority and which the human mind tries to understand it. First formulated by Aristotle.

Pyrrho of Ellis
Scepticism: philosophical view that does not deny the existence of a physical reality, but denies that humans can have reliable knowledge of it; first formulated by Pyrrho of Ellis.
Humans must suspend judgment on all matters of reality.

Augustine

Augustine (354-430CE)
True knowledge was knowledge based on God’s revelations.
This view became dominant until well into the seventeenth century.

Interaction between theory and experiment: the scientific revolution

Galilei’s thought experiments

Galilei is usually credited as the person who convinced the world of the importance of observation and experimentation for the acquisition of knowledge.
But Galilei might in reality be a transition figure steeped in the Aristotelian tradition.

• Galilei referred more often to thought experiments than real experiments in his writings
• Galilei may have derived his law of motion from real