The Quine-Putnam indispensability argument in the philosophy of mathematics urges us to place mathematical entities on the same ontological footing as other theoretical entities essential to our best scientific theories. Recently, the argument has come under serious scrutiny, with many influential philosophers unconvinced of its cogency. This book not only outlines the indispensability argument in considerable detail but also defends it against various challenges.

A famous ecologist and a philosopher of science team up to offer a fresh new approach to population biology and ecology. Challenging the traditionally accepted Lotka-Volterra model, which is based on predator-prey interactions, this new model emphasizes maternal effects, specifically the significance of a mother's interest in the success of her female offspring.