Scepticism and Animal Faith (1923) is a later work by Spanish-born American philosopher George Santayana.

Scepticism is Santayana's major treatise on epistemology; after its publication, he wrote no more on the topic.

Let him clean better, if he can, the windows of his soul, that the variety and beauty of the prospect may spread more brightly before him.While Santayana acknowledges the importance of skepticism to philosophy, and begins by doubting almost everything; from here, he seeks to find some kind of epistemological truths.

He makes this pragmatic claim by asserting that men do not live by the principles of idealism, even if it is true.

We have functioned for eons without adhering to such principles, and may continue, pragmatically, as such.