Although the idea expressed in cogito ergo sum is widely attributed to Descartes, he was not the first to mention it.
Spanish philosopher Gómez Pereira in his 1554 work De Inmortalitate Animae, published in 1749, wrote "nosco me aliquid noscere, et quidquid noscit, est, ergo ego sum" ("I know that I know something, anyone who knows exists, then I exist") [REF].