The Humoral Theory, originating in ancient Greece, suggests that mental illness is caused by an imbalance of four bodily humors: blood, phlegm, yellow bile, and black bile.

The Biological Theory emphasizes the role of genetic factors and neurochemical imbalances in the development of mental illness.

Sigmund Freud is widely known for his contributions to the Psychodynamic Theory, which focuses on unconscious conflicts and early childhood experiences as the root of mental illness.

The Cognitive-Behavioral Theory focuses on the interaction between thoughts, emotions, and behaviors in the context of mental illness.

The Humanistic Theory highlights the significance of personal growth, self-actualization, and the individual's capacity for change in addressing mental illness.

The Cognitive-Behavioral Theory emphasizes the role of faulty or distorted thinking patterns, known as cognitive distortions, in the development and maintenance of mental illness.

The Social Learning Theory suggests that mental illness can be learned through observational learning and imitation of others' behaviors, attitudes, and beliefs.

The Sociocultural Theory focuses on the influence of social and cultural factors, such as poverty, discrimination, and cultural norms, on the development of mental illness.

The Diathesis-Stress Model suggests that mental illness is caused by the interaction between genetic predisposition and environmental stressors.

The Biopsychosocial Theory emphasizes the interplay of biological, psychological, and social factors in the development and treatment of mental illness.

The Transdiagnostic Approach aims to identify and address common underlying mechanisms that contribute to various mental disorders, rather than treating each disorder independently.

Traditional Chinese Medicine Theory views mental illness as a result of an imbalance between yin and yang, the opposing forces that govern the body and mind.

The Dual Diagnosis Approach focuses on the assessment and treatment of individuals with co-occurring mental and physical disorders, recognizing the complex interplay between these conditions.

Attachment Theory explores the role of early childhood experiences and attachment styles in shaping an individual's susceptibility to mental illness.

The Positive Psychology Approach aims to enhance well-being, resilience, and positive emotions as a means of preventing and treating mental illness.