On account of the fact the order of the lines is inverted in the movement from the first to the second set of eight lines, we refer to the second set of eight lines as a mirror image. The conception of a mirror image does not imply a direct correlation but a correlation in difference, which emerges from the inversion of the positioning of the lines in the second set of eight lines. Proceeding from this structure constituted of a pairing of two sets of eight lines, which represent mirror images of each other, in inverted form, a further fourteen patterns are developed.

The first sixteen patterns thus developed are known as the major Odu or organisational categories of Ifa. From this major sixteen Odu or organisational categories, are developed a further two hundred and fifteen categories. The process through which these are developed consists in a process in which each member or set of the primary or major sixteen Odu is further developed into a another set of sixteen Odu which constitute its derivates, or Omo Odu (children of the Odu).

This process is carried out with each of the primary Odu so that a complete set of two hundred and fifty-six Odu, consisting of the primary sixteen and their derivatives, emerges.

This ordering and development of the Odu, organised in terms of graphic signs represented by patterns of lines organized in formations that demonstrate a numerical value, constitutes the mathematical structure of the Ifa system.[SEE IFA DIVINATION AND COMPUTER SCIENCE- LONGE’S INAUGURAL BOUGHT FROM UI.GET YOUR COPY FROM OHONBAMO.SEE IF YOU CAN GET IT THROUGH INTERLIBRARY LOAN]