to the element of provocation, or to both these elements in the legend of Oedipus. These elements of provocation and involuntariness are most important for the legal intelligibility of the _Oedipus Coloneus_, as we shall see later.[234] At present we wish to emphasise the fact that this legend, like the legend of Orestes, became, so to speak, ‘Apollinised’ in post-Homeric times. Such transitions are only intelligible if we assume a connexion between Apollo and ‘pollution.’ We may infer that, in the post-Homeric legend, Apollo took a lenient view of the guilt of Oedipus, from the fact that, in the _Oedipus Coloneus_, the responsibility for his continued exile is laid not upon Apollo, but upon Kreon and the sons of Oedipus, who wish to enjoy the vacant throne of Thebes.[235] According to Euripides,[236] Oedipus’ sons imprisoned him, but Kreon drove him into exile. In the _Orestes_ of Euripides[237] it is Apollo who saves Orestes from the wrath of the Argives who have condemned him to death. Apollo decrees that, when Orestes has endured a period of exile and has submitted to a trial at Athens, the Argives must accept as their king a man whom they had already deemed worthy of an ignominious death! In the _Electra_ of Euripides,[238] Castor and Pollux refer, by way of prophecy, to the fact that Apollo will ultimately secure Orestes’ deliverance from the Erinnyes. In the _Ion_ of Euripides[239] the Pythian priestess of Apollo commands Ion not to slay Creusa, who had attempted to poison him, and who otherwise would have urged in vain her plea of self-defence and the sacredness of her sanctuary. In the _Andromache_ of Euripides, Apollo is criticised for having permitted the slaying of Neoptolemus within the precincts of the temple at the hands of Orestes and the Delphians. The Messenger says[240]: ‘Thus has the Lord who gives oracles to others, who is the umpire for all men of what is right, requited the son of Achilles ... like any wicked mortal, he stores in his memory an ancient quarrel.’ Thus the conception of homicide as a pollution permeates all Greek tragedy: however various the legends, however different the localities to which they refer, they all breathe the same Apolline atmosphere. We have already[241] quoted Herodotus’ opinion as to the universality of the ‘purgation’ rites by which the pollution of homicide was cleansed. If it be true, moreover, that the laws which regulated the historical Greek treatment of homicide were more or less identical in all the more important and advanced Greek States, would not this fact suggest that the origin of these laws must be sought, not in the genius of occasional local legislators, but rather in the simultaneous universal operation of identical causes? One of these causes, we believe, was the doctrine of pollution.