Modern psychology fragments the mind into separate concepts: trauma, personality, habits, cognition. This book proposes a radical unifying metaphor: the Mental Biome. Just as your gut contains a complex ecosystem of bacteria affecting your physical health, your mind contains a complex ecosystem of internalized voices and patterns affecting your mental health. This ecosystem can become imbalanced-leading to invasive species (harsh self-criticism), monocultures (rigid thinking), or depleted landscapes (depression). By understanding your mind as a living ecosystem requiring care rather than control, you can restore balance through principles borrowed from ecological science.