Nevertheless, even with most source writings of those later considered heretics destroyed, evidence can be provided that since the first century BC there have been various groups and individuals who have held certain individual Christadelphian beliefs or similar ones. For example, all the distinctive Christadelphian doctrines (with the exception of the non-literal devil), down to interpretations of specific verses, can be found particularly among sixteenth century Socinian writers (e.g. the rejection of the doctrines of the trinity, pre-existence of Christ, immortal souls, a literal hell of fire, original sin). Early English Unitarian writings also correspond closely to those of Christadelphians. Also, recent discoveries and research have shown a large similarity between Christadelphian beliefs and those held by Isaac Newton who, among other things, rejected the doctrines of the trinity, immortal souls, a personal devil and literal demons. Further examples are as follows: