The stone age person had significant contact with the natural world and, with this, the sky. By night many bright points appear upon the black dome of the celestial sphere at night, as a fixed pattern, and the moon is then like a weaker version of the sun. Day begins when the sun appears on the eastern horizon (to define morning) and sets in the west (to define evening). It would therefore soon become clear, to stone age observers, that the starry points we now call stars move like the sun by rising in the east and setting in the west.
A six-fold hexad of three dimensions as they affected megalithic astronomers
Hyparxis (In Greek, ὕπαρξις) means 'essential nature' and is the Neoplatonic term for the summit, beginning, or hierarch of a hierarchy, as follows: The word is particularly used by the Neoplatonist, Proclus who uses it to mean "the summit of any nature, or blossom, as it were, of its essence."
Eternity is cyclic and often symbolized by the image of a snake swallowing its own tail, known as the Ouroboros (or Uroboros). The circle is also commonly used as a symbol for eternity, as is the mathematical symbol of infinity, .
Time is the fourth dimension and a measure in which events can be ordered from the past through the present into the future, and also the measure of durations of events and the intervals between them.
This recurrence, of celestial luminaries rising in the east and setting in the west, is generated by the rotation of the earth and, in the late stone age, marked bones and other objects indicate that longer time periods such as the lunar month were being counted for many thousands of years, as one mark per day.
The lunar month was therefore the original example of cyclicity, through which the stone age could usefully count days so as to somewhat predict the future appearance and disappearance of the moon at night, and quite possibly discover connections between the tides, and other cycles relating to the moon.
The arrival of the sun on the eastern horizon is however not constant as the sun moves towards the north in summer and towards the south in winter, leading to the variations in climate throughout the solar year of 365 days, a cyclicity best identified in the movement of the horizon events (sunrise and sunset) of the sun. The moon also rises further north and south but over a shorter period, this corresponding to the moon's orbit of the earth every 27 1/3 days.
The megalithic clearly studied these variations (of the alignment of horizon events, of sun and moon) within suitably large monuments, these therefore commemorating, through definite alignments to the horizon,the cyclic journey of the solar year and lunar orbital variations, whilst also preserving (for us) the astronomical practices of the megalithic.
The cosmic cycles seen from earth are called synodic periods because they only exist when the observer's motion (due to a moving and rotating earth) are factored in. Synodic periods could be counted in days by the megalithic astronomers and (when each day was given a unit of constant length) a geometrical line resulted. Such counted lines physically represented the duration of a given synodic period, against which other (synodic counted) lengths (representing other cosmic cycles) were compared, within the geometric form of a right triangle.
Synodic periods would then have been found to hold significant numerical ratios between each other and these invariant ratios can be seen to follow simple geometrical or harmonic rules, some of which can be recognised within the design of megalithic monuments. One example of a geometrical synodic ratio is that the length of the solar year relative to the lunar year is identical to the length of the diagonal of a four squares rectangle relative to its four unit long side. An example of musical harmonic ratio is the length of the Jupiter synod relative to the lunar year is the whole tone ratio of 9/8.
Geometrical invariants based upon synodic counted lengths are certainly visible in megalithic monuments, alongside the alignments to the horizon. There is also evidence of alignments pointing to the northern horizon, where the only objects to align to were the circumpolar stars which display directly the rotation of the earth and the recurrence of the day due to that rotation causing sunrise in the east and sunset in the west and the movement of the celestial sphere.