The Problems of Philosophy

The Problems of Philosophy is one of the canonical short introductions to analytic philosophy and shaped its pedagogical tradition for decades.

"Philosophy, though unable to tell us with certainty what is the true answer to the doubts which it raises, is able to suggest many possibilities." (Problems ch. 15)

Russell's mature pre-war realism — physical objects exist mind-independently, universals are real but non-spatial — is one of the most rigorous statements of early-twentieth-century analytic realism.

"Universals... do not exist in the same sense as that in which thoughts and feelings exist." (Problems ch. 9)

The doctrine of knowledge by acquaintance — knowledge's foundation in direct experience of sense-data, universals, and the self — is the most rigorous statement of Russellian empiricism.

"All our knowledge, both knowledge of things and knowledge of truths, rests upon acquaintance as its foundation." (Problems ch. 5)

Although Russell pre-dates logical positivism, his sense-data epistemology and his commitment to logical analysis prepared the way for the Vienna Circle.

"The chief value of philosophy... lies in its very uncertainty." (Problems ch. 15)

Russell's sense-data theory of perception — we are directly aware of sense-data, not of physical objects themselves — places him at the threshold of phenomenalism.

"It is by no means easy to know what we mean by a physical object." (Problems ch. 2)

Russell's Platonist realism about universals is the philosophical position most directly descended from Plato's Forms.

"Universals are eternal and changeless." (Problems ch. 9, paraphrasing)

Analytic-philosophical tradition.