Joe:<br><br>Thanks for the reply. However, none of those sources really offer what I'm looking for (1 link is broken, 2 only have Spinoza's name one each in a list of the philosophers of his time and the other 2 only explain his statements).<br><br>I've actually read and comprehended Spinoza's Ethics. What I can't do is refute his argument.<br><br>One problem is the "mind-body parallelism" noted in your post. Spinoza notes in the Ethics "P2: Two substances having different attributes have nothing in common with one another." From this he concludes that a thinking substance cannot be the cause of an extended substance. As God (as He is commonly perceived) is not an extended substance, He cannot be the cause of the universe. Therefore, Spinoza must conclude that God is consubstantial with the physical universe (or else He could not be its cause). This also has implications in the mind/body duality. If mind is a thinking substance, and body an extended substance, how do the two affect each other? Spinoza concludes it is impossible (therefore, mind and body are consubstantial). Ultimately, Spinoza uses this one statement as the basis of his monism (the other major proposition being "P5: In nature there cannot be two or more substances of the same nature or attribute" leading to "P7: Every substance is necessarily infinite").<br><br>I believe that Hodge has a good beginning to addressing the necessity of infinite substances well by stating that the existence of an infinite line does not preclude the existence of a finite line (line segment, to be technical -- if my memory of geometry serves me). However, that only deals with Spinoza's definition of infinite; it doesn't deal with Spinoza's question of how one distinguishes between to substances of the same type (P5 of the first part of the Ethics).<br><br>I also still haven't found a good answer to the question of the relations of substances of different attributes. That is, if our mind is spiritual (a spiritual or thinking substance), then how does it affect the body (an extended substance)? Also, there is the issue of God creating and interacting with a substance completely unlike Himself (I think this would be solved if the previous question could be answered however).<br><br>So, if you or somebody else knew of something dealing with those issues, that is what I really need (to be quite specific).<br><br>Take care,