We will continue with the Greco article on Thursday.

Thought question for Thursday.

The skeptical argument we have been examining concludes that we do not know anything that would count as a basic observation statement about the external world. Consider this modal argument.

1. If it is possible that I am a brain in a vat, it is possible that I do not have hands.
2. It is possible that I am a brain in a vat.
3. Therefore, it is possible that I do not have hands.

(1) Reconstruct this argument by changing the first premise so that this becomes a modus tollens argument.

(2) Compare this argument to the original skeptical argument, noticing in particular that it makes no reference to knowledge at all. What additional proposition will secure the conclusion of the skeptical argument?

(3) Do you think the resulting argument is stronger or weaker than the usual form of the skeptical argument. Explain.