Suicidology is the scientific study of suicidal behaviour, the causes of suicidalness and suicide prevention. There are many different fields and disciplines involved with suicidology, the two primary ones being psychology and sociology.Most suicidologists think about the history of suicide in terms of courts, church, press, morals, and society. In Ancient Greece, there were several opinions about suicide. It was tolerated and even lauded when committed by patricians (generals and philosophers) but condemned if committed by plebeians (common people) or slaves. In Rome, suicide was viewed rather neutrally, even positively because life was held cheaply. During early Christianity, excessive martyrdom and a penchant toward suicide frightened church elders sufficiently for them to introduce a serious deterrent. Suicide was thought of as a crime because it precluded possibility of repentance, and it violated the sixth commandment which is Thou shall not kill. During this time, St. Thomas Aquinas emphasized that suicide was a mortal sin because it disrupted God's power over man's life and death. However, nowhere in the Judeo-Christian Bible is there a directive forbidding suicide. This belief took hold and for hundreds of years thereafter played an important part in the Western view of suicide. Over the last 200 years, the main focus of suicide has moved from accusations that it is a sin to effort at compassion, understanding, and prevention