"The Problems of Philosophy" by Bertrand Russell is a book published in 1912 that attempts to create a brief, accessible guide to philosophy's fundamental questions. Can we prove an external world exists? Can we validate cause and effect or justify morality? Russell argues philosophy cannot definitively answer these questions, focusing instead on theories of knowledge and exploring how we know anything at all. He introduces his famous distinction between knowledge by acquaintance and description, drawing on insights from Plato, Descartes, Hume, and Kant to guide both general readers and scholars through philosophical inquiry.