What Can We Really Know? Russell's "The Problems of Philosophy"

Bertrand Russell’s The Problems of Philosophy is a small classic, one of the best short introductions to philosophy ever written. In barely more than a hundred pages, Russell takes the reader by the hand and walks them into the deepest questions of epistemology and metaphysics, starting from the most ordinary object imaginable: a table. What can we really know about this table in front of us? The question seems trivial, until Russell shows, with beautiful clarity, how it opens onto the hardest problems in philosophy, the nature of reality and appearance, the existence of matter, the limits of knowledge. It is a model of philosophical writing: lucid, rigorous, and genuinely thrilling, demonstrating how the most familiar things, looked at closely, become profoundly strange.

Here is what The Problems of Philosophy taught me about appearance and reality, about the strangeness of the ordinary, and about the value of philosophy itself.

Key takeaways

• Appearance versus reality: what we directly perceive differs from what things are in themselves.
• The humble table opens onto the deepest questions of knowledge and existence.
• “Sense-data” are what we directly experience; the physical object is inferred.
• Certainty is harder than it looks; much of what we “know” rests on assumptions.
• The value of philosophy lies in the questions, which enlarge the mind.

Appearance and reality

Russell begins, brilliantly, with the table. Is there any knowledge in the world so certain that no reasonable person could doubt it? He looks at the table before him, brown, rectangular, solid, and shows how quickly the certainty dissolves. The colour of the table looks different from different angles and in different light; its apparent shape changes as we move; its texture, under a microscope, is not smooth at all. What we directly experience, Russell argues, are not the table itself but what he calls “sense-data”: the particular patches of colour, shapes, and sensations that appear to us. The “real” table, the physical object supposedly causing these appearances, is something we infer, not something we directly perceive. And this opens the great question: does the real table even exist, independent of our perceptions, and if so, how can we know anything about it? The familiar gap between appearance and reality, between how things seem and how they are, turns out to be a chasm.

The strangeness of the ordinary

What I love about Russell’s method is how he makes the most ordinary thing become profoundly strange. We go through life utterly confident that there is a real, solid table in front of us, that the external world exists more or less as we perceive it. Russell does not deny this, but he shows how much we are simply assuming, how the existence of matter independent of our minds, the reliability of our senses, the very idea of a physical world behind our perceptions, are not certainties we have proved but reasonable beliefs we hold, which, on close examination, are far harder to justify than we ever imagined. This is the peculiar gift of philosophy: to take what we take completely for granted and reveal it as genuinely mysterious. After reading Russell on the table, I could not look at the ordinary objects around me in quite the same way; the solid, obvious world had become a fascinating question.

The value of philosophy

Russell ends the book with a beautiful chapter on the value of philosophy itself, which answers the practical sceptic who asks what all this questioning is good for. The value of philosophy, Russell argues, is to be sought largely not in its answers, which remain uncertain, but in its questions. Philosophy keeps alive our sense of wonder; it frees us from the “tyranny of custom,” the narrow assumptions of everyday life and prejudice; it enlarges our conception of what is possible; and, through contemplating the vastness of the universe and the great questions, it expands the mind and even, Russell suggests, makes us greater, more universal in our thinking, less imprisoned in our small, private concerns. We study philosophy, he says, not for definite answers, since few can be known, but for the sake of the questions themselves, which enrich our intellectual imagination and free us from confident, narrow certainty. This is, to me, one of the finest defences of the philosophical life ever written, and a fitting close to a book about how much, and how little, we can really know.

What I’m taking with me

The Problems of Philosophy is the perfect short introduction to philosophy, and a model of how to think clearly about hard things. What I am taking from Russell is the deep distinction between appearance and reality, opened up by the humble example of the table; his gift for making the ordinary world strange and fascinating again; and his luminous defence of the value of philosophy as lying in its questions, which keep wonder alive and free the mind from the tyranny of custom. Above all, the book leaves me with a renewed sense that the familiar world is genuinely mysterious, and that the willingness to keep asking “but how do I really know?” is not idle but enlarging, a way of remaining awake.

Frequently asked questions

What is The Problems of Philosophy about?

It is Bertrand Russell’s short, classic introduction to philosophy, using the example of a table to explore deep questions about appearance and reality, the existence of matter, the limits of knowledge, and the value of philosophy itself.

What are “sense-data” in Russell?

The immediate contents of our perception, the particular colours, shapes, and sensations we directly experience, as opposed to the physical object itself, which Russell argues we infer rather than directly perceive.

What does Russell say is the value of philosophy?

That its value lies chiefly in its questions, not its answers. Philosophy keeps wonder alive, frees us from the tyranny of custom and narrow assumptions, and enlarges the mind by contemplating the great questions of existence.

References & further reading

1. Russell, Bertrand. The Problems of Philosophy. Williams & Norgate, 1912.
2. Russell, Bertrand. A History of Western Philosophy. Simon & Schuster, 1945.
3. Grayling, A. C. Russell. Oxford University Press, 1996.