Sufficient Reason and the Causal Argument for Monism

What is the role of the principle of sufficient reason in Baruch Spinoza’s ontological proof for God’s existence? Is this role identical within Spinoza’s early work on method, the Treatise on the Emendation of the Intellect, and his magnum opus, the Ethics? This paper argues affirmatively that the methodology employed within the Ethics is consonant with that method found within the Treatise, and this claim is substantiated through an engagement with the influential works of Don Garrett and Aaron Garrett. It is also demonstrated through an original reconstruction of the Treatise itself. In this reconstruction, basic premises are identified which can validly prove Spinoza’s intended conclusion of substance monism. It is finally determined that what the Treatise and the Ethics share, specifically, is a methodology which begins with non-nominal definitions that denote the real, sufficient causes of their respective objects. However, at certain junctures, this methodology is expressed with greater consistency within the Treatise as opposed to within the Ethics. Evidence for this will be provided from the primary texts themselves and from the subsequent analyses of Don Garrett and Aaron Garret as well.