Aristotle based his classification system off of observations of animals, and used physical characteristics to divide animals into two groups
 
        
        
        
Explanation: 
An autoimmune disorder occurs when the body sees it's own cells as foreign antigens and begins to attack them.
The treatment depends on the particular autoimmune disorder; however, the mainstay of treatment is the use of IMMUNOSUPPRESSIVE MEDICATION. Examples include corticosteroids (such as prednisone) and nonsteroid drugs such as azathioprine, cyclophosphamide, mycophenolate, sirolimus, or tacrolimus.