tet·rad Noun /ˈteˌtrad/
tetrads plural
tetrads plural
- A group or set of four
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| The four sons of Horus in their protective role on the coffin of Psusennes. Egyptian Museum in Cairo. Egypt. |
In Egyptian symbolism the number four frequently signified the four cardinal directions and hence a kind of spatial or geographic totality. This significance is seen in the four "races" of mankind; Egyptians (north), Near Easterners (east), Nubians (south) and Libyans (west) depicted in some New Kingdom tombs. It is also apparent in a number of groupings of four deities, such as the four supports of the sky which may be personified as four individual deities or groups of deities aligned with the four points or quarters of the heavens.
The connection is strong enough, in fact, that even when groups of four deities do not seem to originally have this symbolic significance it may become attached to them. Thus the mortuary deities known as the four sons of Horus may some times be aligned geographically in representational contexts although this is not always the case. While the concept of completeness associated with the number four may have sprung entirely from the totality encompassed by the concept of the four cardinal points, the symbolic use of the number is frequently one of completion without any specific directional overtones at all.
In the underworld books four forms of a given god or groups of four deities are frequently found and thus depicted in vignettes in the papyri and decorations of the royal tombs. An interesting example of this king of tetrad is found in Ramesside times when the god Seth was elevated to the extent that he was sometimes named along with three great deities Amun, Ra and Ptah. The four divisions of the Egyptian army were named after Seth and the other three deities in a group which clearly could be conceived as holding the symbolism of tactical or strategic completeness. While the members of dyads and triads are usually distinguished from one another in representational works, the deities found in groups of four are often undifferentiated - showing their apparently more "generic" nature.
