The motive for instituting the eight years' cycle was religious, not practical or scientific.
We are informed, and may readily believe, that the motive which led the Greeks to adopt the eight years' cycle was religious rather than practical or scientific: their aim was not so much to ensure the punctual despatch of business or to solve an abstract problem in astronomy, as to ascertain the exact days on which they ought to sacrifice to the gods. For the Greeks regularly employed lunar months in their reckonings,289 and accordingly if they had dated their religious festivals simply by the number of the month and the day of the month, the excess of eleven and a quarter days of the solar over the lunar year would have had the effect of causing the festivals gradually to revolve throughout the whole circle of the seasons, so that in time ceremonies which properly belonged to winter would come to be held in summer, and on the contrary ceremonies which were only appropriate to summer would come to be held in winter. To avoid this anomaly, and to ensure that festivals dated by lunar months should fall at fixed or nearly fixed points in the solar year, the Greeks adopted the octennial cycle by the simple expedient of intercalating three lunar months in every period of eight years. In doing so they acted, as one of their writers justly pointed out, on a principle precisely the reverse of that followed by the ancient Egyptians, who deliberately regulated their religious festivals by a purely lunar calendar for the purpose of allowing them gradually to revolve throughout the whole circle of the seasons.290
In early times the regulation of the calendar is largely an affair of religion.
Thus at an early stage of culture the regulation of the calendar is largely an affair of religion: it is a means of maintaining the established relations between gods and men on a satisfactory footing; and in public opinion the great evil of a disordered calendar is not so much that it disturbs and disarranges the ordinary course of business and the various transactions of civil life, as that it endangers the welfare or even the existence both of individuals and of the community by interrupting their normal intercourse with those divine powers on whose favour men believe themselves to be absolutely dependent. Hence in states which take this view of the deep religious import of the calendar its superintendence is naturally entrusted to priests rather than to astronomers, because the science of astronomy is regarded merely as ancillary to the deeper mysteries of theology. For example, at Rome the method of determining the months and regulating the festivals was a secret which the pontiffs for ages jealously guarded from the profane vulgar; and in consequence of their ignorance and incapacity the calendar fell into confusion and the festivals were celebrated out of their natural seasons, until the greatest of all the Roman pontiffs, Julius Caesar, remedied the confusion and placed the calendar of the civilised world on the firm foundation on which, with little change, it stands to this day.291
The quadriennial period of games and festivals in Greece was probably arrived at by bisecting an older octennial period.
On the whole, then, it appears probable that the octennial cycle, based on considerations of religion and on elementary observations of the two great luminaries, dated from a very remote period among the ancient Greeks; if they did not bring it with them when they migrated southwards from the oakwoods and beechwoods of Central Europe, they may well have taken it over from their civilised predecessors of different blood and different language whom they found leading a settled agricultural life on the lands about the Aegean Sea. Now we have seen reasons to hold that the two most famous of the great Greek games, the Pythian and the Olympian, were both based on the ancient cycle of eight years, and that the quadriennial period at which they were regularly celebrated in historical times was arrived at by a subdivision of the older octennial cycle. It is hardly rash, therefore, to conjecture that the quadriennial period in general, regarded as the normal period for the celebration of great games and festivals, was originally founded on elementary religious and astronomical considerations of the same kind, that is, on a somewhat crude attempt to harmonise the discrepancies of solar and lunar time and thereby to ensure the continued favour of the gods. It is, indeed, certain or probable that some of these quadriennial festivals were celebrated in honour of the dead;292 but there seems to be nothing in the beliefs or customs of the ancient Greeks concerning the dead which would suggest a quadriennial period as an appropriate one for propitiating the ghosts of the departed. At first sight it is different with the octennial period; for according to Pindar, the souls of the dead who had been purged of their guilt by an abode of eight years in the nether world were born again on earth in the ninth year as glorious kings, athletes, and sages.293 Now if this belief in the reincarnation of the dead after eight years were primitive, it might certainly furnish an excellent reason for