Читать книгу Philosophy For Dummies - Tom Morris - Страница 50

Some curmudgeonly ancient thinkers like Carneades boldly declared that, “Knowledge is impossible.” Others averred, a tad bit more humbly, merely that “Nothing is known.” But what’s the most obvious, embarrassing question you could ask such a person? Right: “How do you know that?” Another related negative position might maintain only that, “No beliefs are rational.” But all these claims are examples of propositions that, in one way or another, are self-defeating or self-undermining. Consider these statements:

 No propositions are true.

 This sentence is not made up of words.

 No, I don’t speak any known language.

All these statements are self-undermining as well. Self-undermining sentences or statements fall into these categories: those that can’t possibly be true; those that can’t be rational to hold; and those that in some way defeat themselves when expressed. They are linguistic curiosities, but not much else.

The skepticism that is consulted and examined here is not self-defeating like some form of dogmatic naysaying. Proper skeptics do not deny. They just hesitate to affirm, and they question the affirmations that everyone else naturally make. The current world of social media, commercial hype, and nonstop political propaganda could use a little more healthy skepticism.

This is the ancient heritage of skepticism. But the use of skeptical questioning in this chapter is a bit different. What you’ll see here isn’t directed toward the attainment of spiritual peace. It’s about intellectual enlightenment. In other parts of the book, you can put this into service with matters of the spirit. (See for example chapters 10-12, 13-15, 16-18 and 19-21.) But for now, the task is merely to probe into the foundations of what normally is considered to be human knowledge. There are some important realizations to be had. You’ll see what Cicero had in mind when he once intimated, “By doubting, we come at the truth.”