Hans Eysenck proposed a type-cum-trait approach to personality that incorporated both types and traits. He believed there were three fundamental personality factors: extraversion vs introversion, neuroticism vs emotional stability, and psychoticism vs impulse control. These factors determine four basic temperament types - melancholic, choleric, phlegmatic, and sanguine. Eysenck's theory contributed to research in criminology, education, genetics, psychopathology, and political ideology. It argued that personality traits are determined by heredity.