Questions on Descartes' Principles:

1.  Paragraph IV of Part II of Descartes's Principles (p. 199) 
characterizes the nature or essence of matter as extension.  What 
properties are included in this nature or essence?  Which are 
excluded?

2.  Descartes here gives an argument that hardness does not belong to 
the nature or essence of matter.  What is this argument?

3.  Descartes also says that the same reasoning would apply to 
weight, color, and all other sensible properties.  How would this 
argument work for color, say?  Compare paragraph CXCVIII of Part IV 
(pp. 233-4) and Discourse I of the Dioptrics (pp. 241-2).

4.  In paragraph V (pp. 199-200) Descartes describes an objection to 
his doctrine of matter based on the possibility of condensation and 
rarefaction.  What is this objection?  How does Descartes reply to it 
in paragraphs VI, VII (pp. 200-1)?

5.  In paragraph XI (pp. 202-3) Descartes gives another argument that 
space and body (matter) are identical.  What is this argument?

6.  Paragraphs XVI-XVIII (pp. 205-6) consider the possibility of a 
vacuum "in the philosophical sense" and reject it.  What is a vacuum 
"in the philosophical sense"?  Why does Descartes reject it?

7.  Paragraphs XXI-XXIII (pp. 207-8) argue that celestial and 
terrestrial matter cannot differ in nature or essence (thereby 
implicitly rejecting Aristotle!).  What is Descartes's argument for 
this?

8.  Paragraphs XXXVII-XXXIX (pp. 216-18) state Descartes's version of 
the law of inertia.  How does Descartes state this law?  How does it 
differ from Galileo's version?

9.  How does Descartes's version of the law of inertia here rest on 
his view of God's creation of matter?