First published in 1892, this important work by the mathematician Karl Pearson (1857-1936) presents a thoroughly positivist account of the nature of science. Pearson claims that 'the scientific method is the sole gateway to the whole region of knowledge', rejecting additional fields of inquiry such as metaphysics. He also emphasises that science can, and should, describe only the 'how' of phenomena and never the 'why'. A scholar of King's College, Cambridge, and later a professor at King's College and University College London, Pearson made significant contributions to the philosophy of science. Including helpful chapter summaries, this book explores in detail a number of scientific concepts, such as matter, energy, space and time. The work influenced such thinkers as Albert Einstein, who considered it to be essential reading when he created his study group, the Olympia Academy, at the age of twenty-three.