Abstract
What is the role of the principle of sufficient reason inBaruch Spinoza’s ontological proof for God’s existence? Is this roleidentical within Spinoza’s early work on method, the Treatise on theEmendation of the Intellect, and his magnum opus, the Ethics? This paperargues affirmatively that the methodology employed within the Ethics isconsonant with that method found within the Treatise, and this claim issubstantiated through an engagement with the influential works of DonGarrett and Aaron Garrett. It is also demonstrated through an originalreconstruction of the Treatise itself. In this reconstruction, basic premisesare identified which can validly prove Spinoza’s intended conclusion ofsubstance monism. It is finally determined that what the Treatise and theEthics share, specifically, is a methodology which begins with non-nominaldefinitions that denote the real, sufficient causes of their respective objects.However, at certain junctures, this methodology is expressed with greaterconsistency within the Treatise as opposed to within the Ethics. Evidence forthis will be provided from the primary texts themselves and from thesubsequent analyses of Don Garrett and Aaron Garret as well.