Show me the cowries and I will show you my arithmetic skills - The voice of my ancestors through the mouth of Adolphus Mann Esq.

On 9th March 1886, members of The Royal Anthropological Institute of Great Britain and Ireland met in London to examine the paper titled: "Notes on the Numeral System of the Yoruba" authored by Adolphus Mann Esq.

The following are some of the excerpts from Adolphus Mann's report regarding the Yoruba Numeral System:

"A superficial knowledge, with a slight attempt at praxis, suffices to understand the peculiarities in the arrangement of these numerals to which analogies in other languages are but rarely found. We light, as it were on a building, which, when viewed from base to summit is not behind our European systems in regularity and symmetry, while the system surpasses them in the aptitude of interIinking the separate members; it stands to them in the same relation as the profusely ornamented Moorish style stands to the more sober Byzantine." (1 page 59 - 60).

Mr Adolphus Mann, in his report postulated that this inspiring Yoruba System originated from the ways cowrie shell currency was counted by the Yoruba traders and business people:

"When a bagful [of cowries] is cast on the floor, the counting person sits or kneels down beside it, takes 5 and 5 cowries and counts silently, 1, 2, up to 20, thus 100 are counted off, this is repeated to get a second 100, these little heaps each of 100 cowries are united, and a next 200 is, when counted swept together with the first. Such sums as originate from counting are a sort of standard money, 20, 100 and then especially 200, and 400 is 4 little heaps of 100 cowries, or 2 each of 200 cowries, representing to the Yorubas the denominations of the monetary values of their country as to us 1/2d., 1d., 3d., 6d., 1s., &c." (1 page 62).

Note:
d = pence
s = shillings

The key point for us is from the first excerpt: "...when viewed from base to summit is not behind our European systems in regularity and symmetry, while the system surpasses them in the aptitude of interIinking the separate members.."

For a British scientist to admit this in 1886 was unheard of! Mr Mann was effectively saying that the Yoruba Numeral System was superior to the Europeans when linking numbers together - "surpasses them [European Systems] in the aptitude of interIinking the separate members".

This is not only phenomenal but it does demonstrate that the Yoruba Numeral system (vigesimal) is not inferior to other Numeral Systems.

Reference:
(1) Mann, Adolphus. 'Notes on the numeral system of the Yoruba nation.' Journal of the Royal Anthropological Institute 16: 60, 1887.