Wittgenstein and Aquinas

Wittgenstein explores the thought that doubt presupposes certainty in the writings collected in On Certainty. Radical doubt, such as Descartes’ skepticism, assumes that every belief must be justified by evidence. But how could justification even begin if everything required justification? At some point, our practices of knowing must rest on things that are not themselves justified by proof. Thus he writes: “The questions that we raise and our doubts depend on the fact that some propositions are exempt from doubt.”

Later commentators call the propositions hinge propositions, after a passage in On Certainty. The world exists. Other people have minds. The past existed. Objects persist when we stop looking. These are examples of hinge propositions. We do not infer them from evidence; they are the background within which evidence and knowledge become possible.

      Knowledge does not begin from absolute uncertainty. We already stand inside a framework of trust in reality.We learn language, reasoning, and inquiry within a form of life where certain things are simply taken as given. Hinge certainties give rise to ordinary beliefs, which in turn are the ground of inquiry and knowledge. Our knowledge is finite and fallible, but it rests on non-propositional trust in the world.

     In my previous entry, I discussed this problem: if my knowledge is finite and partial, how can I really say that I know what x is? Wittgenstein’s answer would be that because knowing takes place within a shared framework where reality is already trusted. You do not first prove that triangles exist or that language refers to real things. Such things are part of the background certainty of our intellectual life. So when you say “I know what a triangle is,” you are not claiming absolute metaphysical comprehension but something more modest but still real: namely, that within our shared practices of reasoning and geometry, the concept triangle discloses aspects of something real. For Wittgenstein, therefore, finite knowledge is not a problem to be solved. It is simply the human condition of knowing. We know things within language, practices – within a shared world. Our knowledge is fallible, thus revisable; it can be deepened over time.

 

 

      Though they come from very different traditions, Aquinas and Wittgenstein converge more than one might expect. For Aquinas, the human intellect participates in the divine light but according to a finite mode; for Wittgenstein, human knowledge operates within forms of life that already trust reality. Both reject the idea that knowledge must begin with absolute certainty. Both reject radical skepticism. Both assume that our intellect is somehow already oriented toward reality. Wittgenstein does emphasize something Aquinas says less about: namely, the role of practice and community. Our certainty about the world arises from how we live and act. We do not prove the existence of the external world; we live in it. As a child we learn to point, to name things, to measure things, count things, etc. Through these practices, the world becomes intelligible. Thus certainty is embedded in life rather than deduced philosophically.

      I get closest to this when I reflect on the role core experiences play in my life. I love my children. I cannot doubt that, cannot assume that it is an illusion masking some biological imperative, for example. That certainty comes ready-made with built in assumptions (hinges) about how the world must be for my love to be real. That hinge gives rise ultimately to other moral hinges like cruelty is wrong. Such beliefs, again, are not derived from scientific evidence. They are part of the moral foundation of our world. So what I was trying to say in the previous entry – that knowledge is not so much a function of correct essential-theoretical definitions but actively participating in a shared disclosure of reality grounded in hinge certainties about the world – I think I learned from both Aquinas and Wittgenstein, different as they are.

      Another philosopher I greatly admire, Raimond Gaita, puts this idea into the forefront of ethics. He suggests that our certainty about the dignity of persons is hinge-like. When we truly see another person, their humanity becomes indubitable in a way that is not the result of argument. This leads to the importance love as a mode of understanding.