1. PHILOSOPHY 100 (Ted Stolze)
Notes on James Rachels,
Problems from Philosophy

2. Chapter Ten: Our Knowledge of the World around Us

3. Four Positions on the Mind’s Relationship to the External World
Direct Realism (Aristotle, the Buddha)
Cartesian Theological Realism
Subjective Idealism (George Berkeley)
The Commonsense View (Indirect Realism)

4. Direct Realism (1)
“Seeing is a way of getting information about the world around us. But it is not a two-step process, in which we first get information about ‘sense-data’ and then move from that to information about the tree. Instead, it is a one-step process of seeing the tree. That’s how we know the tree is there” (p. 133).

5. Direct Realism (2)
Mind <= Physical World

6. An Objection: Cases of Perceptual Ambiguity
Muller-Lyer Illusion
Ponzo Illusion
The Necker Cube
Café Wall Illusion
Ouchi Illusion
Kanizsa Triangle
E.G.Boring, “My Wife and My Mother-In-Law”
Joseph Jastrow’s Duck-Rabbit
Rex Whistler’s Reversible Faces
The Thatcher Illusion

7. Müller-Lyer Illusion

8. Ponzo Illusion

9. The Necker Cube

10. Café Wall Illusion

11. Ouchi Illusion

12. Kanizsa Triangle

13. E.G.Boring, “My Wife and My Mother-In-Law”

14. Joseph Jastrow’s Duck-Rabbit

15. Rex Whistler’s (1905-1944) Reversible Faces

16. The Thatcher Effect/Illusion (An illusion of how it becomes difficult to detect local feature changes in an upside down face, despite identical changes being obvious in an upright face. It was created by Peter Thompson in 1980 and is named after former British Prime Minister Margaret Thatcher, on whose photograph the effect has been most famously demonstrated.)

17. Cartesian Theological Realism (1)
Mind => (Systematic Doubt) => Cogito => God => (Non- deceiving God) => Physical World

18. Cartesian Theological Realism (2)
The Dream and Evil Demon Arguments
Cartesian Argument for the Cogito

19. The Brain in a Vat Thought Experiment
INPUTS => => OUTPUTS

20. Idealism (2)
Mind => (God) => “Physical World” (Phenomenal World)

21. Idealism (I)
Reality is constituted entirely of minds and their ideas, which are mental representations of objects.

22. Objections to Subjective Idealism
Runs contrary to experience (e.g. of dishwashers)
Have to assume, or prove, the existence of a non- deceiving God
Makes scientific, artistic, or political practice unintelligible, e.g. cannot distinguish between appearance and reality
( video)

23. Vision and the Brain
Perception isn’t a passive process: “The mind does not simply record what passes before it; instead, the mind actively interprets experience according to certain built-in principles. Therefore, what we think of as ‘simple’ perception is actually the result of a complicated interpretation of the sensory data” (p. 134).

24. The Commonsense View (1)
“We have experiences such as ‘seeing a tree’ or ‘hearing a cricket’ because our bodies interact with a physical world that includes things like trees and crickets. The world impinges on our sense organs, causing us to have experiences that represent the world to us in a fairly accurate way. The physical world exists independent of us—that is, it would exist even if we didn’t exist, and it continues to exist even when we are not observing it” (p. 137).

25. The Commonsense View (2)
Mind <= Brain <= (Bodily Interaction) <= Physical World

26. Objections to the Commonsense View
“Dissolving World” thought experiment (pp )
Brain in a Vat revisited