This non-technical introduction to ethics explores how we find true or reasonable moral principles which we can apply to concerns and issues in our everyday lives. Torbjorn Tannsjo presents the reader with seven radically different basic moral theories, each of which attempts to provide an ultimate answer to the question of what we ought to do and why. Tannsjo carefully describes each theory, assessing it critically and putting it into historical perspective. The theories covered are: utilitarianism, egoism, deontological ethics, the ethics of rights, virtue ethics, feminist ethics, environmental or ecological ethics. In this second edition: *all arguments are reviewed and clarified throughout *theories examined are now illustrated with the famous 'trolley' cases *a new final chapter addresses the influence of neuroscience and psychology on the formation of our moral intuitions.