1. What fourth condition for knowledge does Pollock first examine?
2. Which examples show that adding this fourth condition is still insufficient?
3. What condition on knowledge is the Tom Grabit example intended to discredit?
4. How are the two examples from Gilbert Harman supposed to differ from the Tom Grabit example?
5. What is the difference between a common knowledge defeater and a readily available defeater?
6. According to Pollock, what are propositions that are socially sensitive?