I mean, we also call extreme aggressive tendencies a mental illness or disorder. In general, the standard in mental illnesses is that in order for a diagnosis

I mean, we also call extreme aggressive tendencies a mental illness or disorder. In general, the standard in mental illnesses is that in order for a diagnosis to be made, the condition must interfere with leading a fulfilling life; a narcissist is only diagnosed with NPD if their narcissism prevents them from achieving their goals in life (hold down a job, maintain relationships, etc).