James Tyler Kent, MD (born in Woodhull, New York, 1849) proved many new remedies. He advocated the use of potencies made on the centesimal scale. Dr Kent introduced the doctrine of 'Series in Degrees' in the treatment of chronic diseases, 'Theory of Octaves', 'Law of Vital Action and Reaction'. He laid importance on mind symptom in treating chronic cases. He taught Materia Medics at the Homoeopathic Medical College of St Louis, from 1881-88, at the School of Homoeopathy, Philadelphia from 1890-99, at Hahnemann Medical College and Hospital, Chicago from 1903-09. His repertory which was published in 1897 remains the most sought after book in homeopathy till date. He died on 6th June 1916 but his contribution are immortal.