In environmental science, experimental design is an extremely important part of the scientific method. When a scientist seeks to prove or disprove a hypothesis, he or she must carefully design the experiment so that it tests only one thing, or variable.
Borderline personality disorder (BPD), also known as emotionally unstable personality disorder, is a long term pattern of abnormal behavior characterized by unstable relationships with other people, unstable sense of self, and unstable emotions.
Borderline personality disorder is a disorder during which a person exhibits unstable moods, behavior and relationships. They are also associated with reckless behavior and suicidal tendencies. Narcissistic personality disorder is a medical condition in which a person exhibits unstable and intense emotions.