Intuitions may seem to play a fundamental role in philosophy: but their role and their value have been challenged recently. What are intuitions? Should we ever trust them? And if so, when? Do they have an indispensable role in science--in thought experiments, for instance--as well as in philosophy? Or should appeal to intuitions be abandoned altogether? This collection brings together leading philosophers, from early to late career, to tackle such questions. It presents the state of the art thinking on the topic.