Example image of eyePlorer eyePlorer map for 'Meaning of life': Intrinsic value (ethics) Purpose Concept Philosophy Science Theology Culture Ideology Afterlife Conceptions of God Consciousness Ethics Existence Existence of God Free will Good and evil Happiness Meaning (linguistics) Ontology Soul Value (philosophy) Empiricism Fact Universe Reality Spirituality Philosophy of science Social psychology (psychology) Terror management theory Limbic system Motivation Neuroscience Pleasure Reward Ventral tegmental area Abiogenesis Anomie Economics Iron-sulfur world theory RNA world hypothesis Sociology Value (economics) Evolution Gene Mutation Natural selection David Haig (biologist) Gene-centered view of evolution George C. Williams Richard Dawkins