Finite verb to be omitted. For example, in the Latin sentence "cogito ergo sum" ("I think therefore I am") the finite verbs "cogito" and "sum" appear without an explicit subject – the subject is understood to be the first-person personal pronoun, and this information is marked by the way the verbs are inflected. In English, finite verbs lacking subjects are normal in imperative sentences: And also occur in some fragmentary utterances: The relatively poor system of inflectional morphology in English makes the central role that finite verbs play be often not so evident. In other languages, finite verbs are the locus of
Cogito, ergo sum distinctiveness of self-evident propositions — to establish true and justified propositions despite having adopted a method of generalized doubt. As a consequence of this demonstration, Descartes considers science and mathematics to be justified to the extent that their proposals are established on a similarly immediate clarity, distinctiveness, and self-evidence that presents itself to the mind. The originality of Descartes's thinking, therefore, is not so much in expressing the "cogito" — a feat accomplished by other predecessors, as we shall see — but on using the "cogito" as demonstrating the most fundamental epistemological principle, that science and mathematics are justified by