Knowing One’s Mind

1. Knowing One’s Mind Joe Cruz Williams College Philosophy & Cognitive Science

2. “Is there any knowledge in the world that is so certain that no reasonable man could doubt it?” — Bertrand Russell The Problems of Philosophy (1912)

3. The question of certainty What is certainty?

4. The question of certainty What is certainty? A claim is certain if it is inconceivable for it to be false.

5. The question of certainty What is certainty? A claim is certain if it is inconceivable for it to be false. (This is not the same as a claim being necessarily true.)

6. The question of certainty Certainty is a reflective, conceptual state.

7. The question of certainty Certainty is a reflective, conceptual state. Are there any plausible candidates for certainty?

8. “I am— I exist: this is certain; but how often? As often as I think...” — René Descartes Meditations on First Philosophy (1614)

9. Thinking as havingexplicit ideas What is thinking?

10. Thinking as havingexplicit ideas “…what is a thinking thing? It is a thing that doubts, understands, conceives, affirms, denies, wills, refuses…”

11. Thinking as havingexplicit ideas — “The cat is on the mat”

12. Thinking as havingexplicit ideas — “The cat is on the mat” Not:

13. Thinking as havingexplicit ideas — “The cat is on the mat” (As purely a thought, or, pure intellection.)

14. Thinking as havingexplicit ideas — “The cat is on the mat” — “Does utilitarianism lead to injustice?” — “I want chocolate” — “The sunset is lovely”

15. Thinking as havingexplicit ideas I.e., having an idea the content of which is explicit, articulate and clear in your mind.

16. Thinking as havingexplicit ideas I.e., having an idea the content of which is explicit, articulate and clear in your mind. (Plus some reflective attitude toward that content)

17. Thinking as havingexplicit ideas Argument for Pure Intellection: Vs. Chiliogon (a thousand-sided figure)

18. Thinking as havingexplicit ideas Can you be wrong about the explicit ideas you are having?

19. Thinking as havingexplicit ideas Can you be wrong about the explicit ideas you are having? Or, could an evil genius deceive you with respect to your explicit ideas?

21. Uncertainty about havingexplicit ideas Of course, you cannot be certain that the cat is on the mat

22. Uncertainty about havingexplicit ideas How about I am certain that I am now thinking: “The cat is on the mat”

23. Uncertainty about havingexplicit ideas But this is not true, let alone certain I am certain that I am now thinking: “The cat is on the mat” Because you are actually thinking “I am now certain that I am thinking: The cat is on the mat.”

24. Uncertainty about havingexplicit ideas So how about “I am now certain I am thinking: The cat is on the mat”

25. Uncertainty about havingexplicit ideas But this is not true, let alone certain “I am now certain that I am thinking: The cat is on the mat” Because you are actually thinking “I am now certain that I am certain that I am thinking: The cat is on the mat.”

26. Uncertainty about havingexplicit ideas Certainty is elusive because pure intellection lags one step behind its object.

27. Uncertainty about havingexplicit ideas Certainty is elusive because pure intellection lags one step behind its object. There is a gap between two acts of thought, and in that gap lies the possibility of error.

28. What about being certain that you have thoughts (even if you cannot be certain which thought you are having)? Uncertainty about havingexplicit ideas

29. What about being certain that you have thoughts (even if you cannot be certain which thought you are having)? But if you can’t be certain which thought you are having, then how can you be certain that you having one? Uncertainty about havingexplicit ideas

30. Uncertainty about havingexplicit ideas Descartes claims that he is certain that he exists, as often as he (explicitly) thinks.

31. Uncertainty about havingexplicit ideas Descartes claims that he is certain that he exists, as often as he (explicitly) thinks. But he cannot be certain how often that is, so he cannot be certain that he exists.

32. Thinking as consciousness What is consciousness?

33. Thinking as consciousness “…it is certain that I seem to see light, hear a noise, and feel heat; this cannot be false, and this is what in me is properly called perceiving, which is nothing else than thinking.”

34. Thinking as consciousness — Tasting chocolate

35. Thinking as consciousness — Tasting chocolate — Seeing the color red — Feeling envy — Experiencing pain

36. Thinking as consciousness I.e., the felt experience of your present sensations.

37. Thinking as consciousness Can you be wrong about how your sensations feel to you?

38. Thinking as consciousness Can you be wrong about how your sensations feel to you? (Not about the words you use, but about the sensations themselves.)

39. Thinking as consciousness Can you be wrong about how your sensations feel to you? Or, could an evil genius deceive you with respect to the way that your sensations feel?

41. Uncertainty about consciousness Being conscious is a (glorious, wondrous, mysterious) capacity that you have.

42. Uncertainty about consciousness Being conscious is a (glorious, wondrous, mysterious) capacity that you have. (And it is likely shared with many non-human animals.)

43. Uncertainty about consciousness Reflecting on your consciousness is a different (glorious, wondrous, mysterious) capacity that you have.

44. Uncertainty about consciousness Reflecting on your consciousness is a different (glorious, wondrous, mysterious) capacity that you have. (And it is likely not shared by many non-human animals.)

45. Uncertainty about consciousness But if consciousness and reflection on consciousness are two different capacities, then an evil genius could ‘enter the gap’ to mislead you.

47. Uncertainty about consciousness

48. Uncertainty about consciousness “I am certain I am now seeing red”

49. What about being certain that you are conscious (even if you can’t be certain what you are conscious of)? Uncertainty about consciousness

50. What about being certain that you are conscious (even if you can’t be certain what you are conscious of)? But if you can’t be certain what you are conscious of, then how can you be certain that you are conscious? Uncertainty about consciousness