1.Consider the skeptic's charge that we can never be confident about the reliability of our normal sources of knowledge (perception, memory, introspection, and reasoning). Does it follow from the fact that we are sometimes mistaken when we rely on these sources that we are always mistaken? How would you respond to the skeptic?
- Does cognitive relativism really imply that persons or cultures are infallible? If so, why would this be a problem for the cognitive relativist? Do you agree with the doctrine's critics on this point? Why or why not?
- Suppose a rationalist declares that scientists can know (without once looking through a telescope) about the physical characteristics of planets in our solar system. Would this be a plausible claim? Why or why not?
- Suppose Locke is right that all we are ever directly aware of is sense data. Would this fact make it impossible to know about external objects? How could we ever know that there is something on the other side of our sense data? Explain how Locke's view can lead to skepticism.
- Berkeley denies the existence of material objects. How would you argue that he is mistaken about this? Hint: Why do you normally assume that material objects exist and are not merely creations of your mind? Why do you assume that the world exists while you are sleeping?
- Do you agree with Descartes (and skeptics) that only propositions that are beyond all doubt can be knowledge? How would you argue against this view?
- The skeptic argues that if we are sometimes mistaken about our beliefs, then it is logically possible that we are always mistaken, and that we therefore do not have knowledge. Evaluate this argument.
- According to Plato, are the ideas of beauty and courage objectively real, or are they notions that we invent in our minds whenever we want to? Do you think these ideas are objectively real? Provide an argument to back up your answer.
- Are you living in the Matrix right now? What argument can you offer to show that you are not in the Matrix? What kind of argument would Descartes offer?
- Consider this statement: All triangles have three sides. Explain how you know it is true even though you haven't examined all triangles in existence.