This thesis attempts to answer the question of what morality actually is, as well as judgements of ‘good’, ‘bad/evil’ from a scientific perspective. I review scientific literature and extract what I think is the best explanation for the foundations of moral judgements, how it evolved and what is judged. Essentially, I derive a fully naturalistic metaethical theory from the scientific literature. This I have called ‘The Power Theory of Morality’ as it shows that morality and judgements of good and bad are based on and can be reduced to power relational evaluations.

From this the thesis naturally flows from the findings of a power-based morality, psychology and metaphysics, to an exploration of Nietzsche’s philosophy, particularly his stance on metaphysics and ethics and its relationship to science. Importantly, Nietzsche relied on the empirical findings and theories of the late nineteenth century, and these have been significantly updated in our time. My thesis goes some way to critiquing his ideas in relation to contemporary understandings of the nature of power and its relationship to morality—a notion vital to Nietzsche’s philosophy. This analysis should provide new perspectives for evaluating Nietzschean ideas, particularly the ‘will to power’ and ‘master/slave’ morality origins. This thesis provides support for the ‘will to power’ as a description of the metaphysical principle underpinning nature, life and psychology and that power is at the heart of ‘moral’, ‘good’, ‘bad/evil’ evaluations, but it argues that Nietzsche’s ‘genealogy’ is implausible and that the ‘master/slave’ distinction requires modification in light of scientific findings since his day.