BEGINNINGS OF ARITHMETIC AND GEOMETRY

The most primitive mathematical activity of man is counting, but here

his first efforts are lost in the obscurity of the past. The lower

races, however, yield us evidence that is not without value. Although

the savage mind is not identical with the mind of primitive man, there

is much in the activities of undeveloped races that can throw light upon

the behavior of peoples more advanced. We must be careful in our

inferences, however. Among the Australians and South Americans there are

peoples whose numerical systems go little, or not at all, beyond the

first two or three numbers. "It has been inferred from this," writes

Professor Boas (_Mind of Primitive Man_, pp. 152-53), "that the people

speaking these languages are not capable of forming the concept of

higher numbers.... People like the South American Indians, ... or like

the Esquimo ... are presumably not in need of higher numerical

expressions, because there are not many objects that they have to count.

On the other hand, just as soon as these same people find themselves in

contact with civilization, and when they acquire standards of value that

have to be counted, they adopt with perfect ease higher numerals from

other languages, and develop a more or less perfect system of

counting.... It must be borne in mind that counting does not become

necessary until objects are considered in such generalized form that

their individualities are entirely lost sight of. For this reason it is

possible that even a person who owns a herd of domesticated animals may

know them by name and by their characteristics, without even desiring to

count them."

And there is one other false interpretation to be avoided. Man does not

feel the need of counting and then develop a system of numerals to meet

the need. Such an assumption is as ridiculous as to assume prehistoric

man thinking to himself: "I must speak," and then inventing voice

culture and grammar to make speaking pleasant and possible. Rather, when

powers of communication are once attained, presumably in their

beginnings also without forethought, man being still more animal than

man, there were gradually dissociated communications of a kind

approaching what numbers mean to us. But the number is not yet a symbol

apart from that of the things numbered. Picture writing, re-representing

the things meant, preceded developmentally any kind of symbolization

representing the number by mere one-one correspondence with

non-particularized symbols. It is plausible, although I have no

anthropological authority for the statement, that the prevalence of

finger words as number symbols (cf. infra) is originally a consequence

of the fact that our organization makes the hand the natural instrument

of pointing.

The difficulty of passing from concrete representations to abstract

symbols has been keenly stated by Conant (_The Number Concept_, pp.

72-73), although his terminology is that of an old psychology and the

limitations implied for the primitive mind are limitations of practice

rather than of capacity as Mr. Conant seems to believe. "An abstract

conception is something quite foreign to the essentially primitive mind,

as missionaries and explorers have found to their chagrin. The savage

can form no mental concept of what civilized man means by such a word as

_soul_; nor would his idea of the abstract number 5 be much clearer.

When he says _five_, he uses, in many cases at least, the same word that

serves him when he wishes to say _hand_; and his mental concept when he

says _five_ is a hand. The concrete idea of a closed fist, of an open

hand with outstretched fingers, is what is uppermost in his mind. He

knows no more and cares no more about the pure number 5 than he does

about the law of conservation of energy. He sees in his mental picture

only the real, material image, and his only comprehension of the number

is, "these objects are as many as the fingers on my hand." Then, in the

lapse of the long interval of centuries which intervene between lowest

barbarism and highest civilization, the abstract and concrete become

slowly dissociated, the one from the other. First the actual hand

picture fades away, and the number is recognized without the original

assistance furnished by the derivation of the word. But the number is

still for a long time a certain number _of objects_, and not an

independent concept."

An excellent fur trader's story, reported to me by Mr. Dewey, suggests a

further impulse to count besides that given by the need of keeping a

tally, namely, the need of making one thing correspond to another in a

business transaction. The Indian laid down one skin and the trader two

dollars; if he proposed to count several skins at once and pay for all

together, the former replied "too much cheatem." The result, however,

demanded a tally either by the fingers, a pebble, or a mark made in the

sand, and as the magnitude of such transactions grows the need of a

specific number symbol becomes ever more acute.

The first obstacle, then, to overcome--and it has already been

successfully passed by many primitive peoples--is the need of fortuitous

attainment of a numerical symbol, which is not the mere repeated symbol

of the things numbered. Significantly, this symbol is usually derived

from the hand, suggesting gestures of tallying, and not from the words

of already developed language. Consequently, number words relate

themselves for the most part to the hand, and written number symbols,

which are among the earliest writings of most peoples, tend to depict it

as soon as they have passed beyond the stage mentioned above of merely

repeating the symbol of the things numbered. W. C. Eells, in writing of

the Number Systems of the North American Indians (_Am. Math. Mo._, Nov.,

1913; pp. 263-72), finds clear linguistic evidence for a digital origin

in about 40% of the languages examined. Of the non-digital instances, 1

was sometimes connected with the first personal pronoun, 2 with roots

meaning separation, 3, rarely, meaning more, or plural as distinguished

from the dual, just as the Greek uses a plural as well as a dual in

nouns and verbs, 4 is often the perfect, complete right. It is often a

sacred number and the base of a quarternary system. Conant (_loc. cit._

p. 98) also gives a classification of the meanings of simple number

words for more advanced languages; and even in them the hand is

constantly in evidence, as in 5, the hand; 10, two hands, half a man,

when fingers and toes are both considered, or a man, when the hands

alone are considered; 20, one man, two feet. The other meanings hang

upon the ideas of existence, piece, group, beginning, for 1; and

repetition, division, and collection for higher numerals.

A peculiar difficulty lies in the fact that when once numbering has

become a self-conscious effort, the collection of things to be numbered

frequently tends to exceed the number of names that have become

available. Sometimes the difficulty is met by using a second man when

the fingers and toes of the first are used up, sometimes by a method of

repetition with the record of the number of the repetition itself added

to the numerical significance of the whole process. Hence arise the

various systems of bases that occur in developed mathematics. But the

inertia to be overcome in the recognition of the base idea is nowhere

more obvious than in the retention by the comparatively developed

Babylonian system of a second base of 60 to supplement the decimal one

for smaller numbers. Among the American Indians (Eells, _loc. cit._) the

system of bases used varies from the cumbersome binary scale, that

exercised such a fascination over Leibniz (_Opera_, _III_, p. 346),

through the rare ternary, and the more common quarternary to the

"natural" quinary, decimal, and vigesimal systems derived from the

use of the fingers and toes in counting. The achievement of a number

base and number words, however, does not always open the way to

further mathematical development. Only too often a complexity of

expression is involved that almost immediately cuts off further

progress. Thus the Youcos of the Amazon cannot get beyond the number

three, for the simplest expression for the idea in their language is

"pzettarrarorincoaroac" (Conant, _loc. cit._, pp. 145, 83, 53). Such

names as "99, tongo solo manani nun solo manani" (i.e., 10, understood,

5 plus 4 times, and 5 plus 4) of the Soussous of Sierra Leone; "399,

caxtolli onnauh poalli ipan caxtolli onnaui" (15 plus 4 times 20 plus 15

plus 4) of the Aztec; "29, wick a chimen ne nompah sam pah nep e chu

wink a" (Sioux), make it easy to understand the proverb of the Yorubas

of Abeokuta, "You may be very clever, but you can't tell 9 times 9."

Almost contemporaneously with the beginnings of counting various

auxiliary devices were introduced to help out the difficult task. In

place of many men, notched sticks, knotted strings, pebbles, or finger

pantomime were used. In the best form, these devices resulted in the

abacus; indeed, it was not until after the introduction of arabic

numerals and well into the Renaissance period that instrumental

arithmetic gave way to graphical in Europe (D. E. Smith, _Rara

Arithmetica_, under "Counters"). "In eastern Europe," say Smith and

Mikami (_Japanese Mathematics_, pp. 18-19), "it"--the abacus--"has never

been replaced, for the tschotue is used everywhere in Russia to-day, and

when one passes over into Persia the same type of abacus is common in

all the bazaars. In China the swan-pan is universally used for the

purposes of computation, and in Japan the soroban is as strongly

entrenched as it was before the invasion of western ideas."

Given, then, the idea of counting, and a mechanical device to aid

computation, it still remains necessary to obtain some notation in which

to record results. At the early dawn of history the Egyptians seem to

have been already possessed of number signs (cf. Cantor, _Gesch. de.

Math._, p. 44) and the Phoenicians either wrote out their number words

or used a few simple signs, vertical, horizontal, and oblique lines, a

process which the Arabians perpetuated up to the beginning of the

eleventh century (Fink, p. 15); the Greeks, as early as 600 B. C., used

the initial letters of words for numbers. But speaking generally,

historical beginnings of European number signs are too obscure to

furnish us good material.

Our Indians have few number symbols other than words, but when they

occur (cf. Eells, _loc. cit._) they usually take the form of pictorial

presentation of some counting device such as strokes, lines dotted to

suggest a knotted cord, etc. Indeed, the smaller Roman numerals were

probably but a pictorial representation of finger symbols. However, a

beautiful concrete instance is furnished us in the Japanese mathematics

(cf. Smith and Mikami, Ch. III). The earliest instrument of reckoning in

Japan seems to have been the rod, Ch'eou, adapted from the Chinese under

the name of Chikusaku (bamboo rods) about 600 A. D. At first relatively

large (measuring rods?), they became reduced to about 12 cm., but from

their tendency to roll were quickly replaced by the sangi (square

prisms, about 7 mm. thick and 5 cm. long) and the number symbols were

evidently derived from the use of these rods:

_ __ ___ ____

|, ||, |||, ||||, |||||, |, ||, |||, ||||.

For the sake of clearness, tens, hundreds, etc., were expressed in the

even place by horizontal instead of vertical lines and vice versa; thus

1267 would be formed

__

- || | ||.

-

The rods were arranged on a sort of chessboard called the swan-pan. Much

later the lines were transferred to paper, and a circle used to denote

the vacant square. The use of squares, however, rendered it unnecessary

to arrange the even places differently from the odd, so numbers like

38057 came to be written

+-------+-------+-------+-------+------+

| | ___ | | | __ |

| ||| | ||| | | ||||| | || |

| | | | | |

+-------+-------+-------+-------+------+

instead of

+-------+-------+-------+-------+------+

| | | | | |

| | | | - | |

| | | | | - | __ |

| ||| | - | | - | || |

| | - | | - | |

| | - | | - | |

| | | | | |

+-------+-------+-------+-------+------+

as in the earlier notation.

Somewhere in the course of these early mathematical activities the

process has changed from the more or less spontaneous operating that led

primitive man to the first enunciation of arithmetical ideas, and has

become a self-conscious striving for the solution of problems. This

change had already taken place before the historical origins of

arithmetic are met. Thus, the treatise of Ahmes (2000 B. C.) contains

the curious problem: 7 persons each have 7 cats; each cat eats 7 mice;

each mouse eats 7 ears of barley; from each ear 7 measures of corn may

grow; how much grain has been saved? Such problems are, however, half

play, as appears in a Leonardo of Pisa version some 3000 years later: 7

old women go to Rome; each woman has 7 mules; each mule, 7 sacks; each

sack contains 7 loaves; with each loaf are 7 knives; each knife is in 7

sheaths. Similarly in Diophantus' epitaph (330 A. D.): "Diophantus

passed 1/6 of his life in childhood, 1/12 in youth, and 1/7 more as a

bachelor; 5 years after his marriage, was born a son who died 4 years

before his father at 1/2 his age." Often among peoples such puzzles were

a favorite social amusement. Thus Braymagupta (628 A. D.) reads, "These

problems are proposed simply for pleasure; the wise man can invent a

thousand others, or he can solve the problems of others by the rules

given here. As the sun eclipses the stars by its brilliancy, so the man

of knowledge will eclipse the fame of others in assemblies of the people

if he proposes algebraic problems, and still more if he solves them"

(Cajori, _Hist. of Math._, p. 92).

The limitation of these early methods is that the notation merely

records and does not aid computation. And this is true even of such a

highly developed system as was in use among the Romans. If the reader is

unconvinced, let him attempt some such problem as the multiplication of

CCCXVI by CCCCLXVIII, expressing it and carrying it through in Roman

numerals, and he will long for the abacus to assist his labors. It was

the positional arithmetic of the Arabians, of which the origins are

obscure, that made possible the development of modern technique. Of this

discovery, or rediscovery from the Hindoos, together with the zero

symbol, Cajori (_Hist. of Math._, p. 11) has said "of all mathematical

discoveries, no one has contributed more to the general progress of

intelligence than this." The notation no longer merely records results,

but now assists in performing operations.

The origins of geometry are even more obscure than those of arithmetic.

Not only is geometry as highly developed as arithmetic when it first

appears in occidental civilization, but, in addition, the problems of

primitive peoples seem to have been such that they have developed no

geometrical formulae striking enough to be recorded by investigators, so

far as I have been able to discover. But just as the commercial life of

the Phoenicians early forced them self-consciously to develop

arithmetical calculation, so environmental conditions seem to have

forced upon the Egyptians a need for geometrical considerations.

It is almost platitudinous to quote Herodotus' remark that the invention

of geometry was necessary because of the floods of the Nile, which

washed away the boundaries and changed the contours of the fields. And

as Proclus Diadochus adds (_Procli Diadochi, in primum Euclidis

elementorum librum commentarii_--quoted Cantor, I, p. 125): "It is not

surprising that the discovery of this as well as other sciences has

sprung from need, because everything in the process of beginning

proceeds from the incomplete to the complete. There takes place a

suitable transition from sensible perception to thoughtful consideration

and rational knowledge. Just as with the Phoenicians, for the sake of

business and commerce, an exact knowledge of numbers had its beginning,

so with the Egyptians, for the above-mentioned reasons, was geometry

contrived."

The earliest Egyptian mathematical writing that we know is that of Ahmes

(2000 B. C.), but long before this the mural decorations of the temple

wall involved many figures, the construction of which involved a certain

amount of working knowledge of such operations as may be performed with

the aid of a ruler and compass. The fact that these operations did not

earlier lead to geometry, as ruler and compass work seems to have

done in Japan in the nineteenth century (Smith and Mikami, index,

"Geometry"), is probably due to the stage at which the development of

Egyptian intelligence had arrived, feebly advanced on the road to higher

abstract thinking. It is everywhere characteristic of Egyptian genius

that little purely intellectual curiosity is shown. Even astronomical

knowledge was limited to those determinations which had religious or

magically practical significance, and its arithmetic and geometry never

escaped these bounds as with the more imaginative Pythagoreans, where

mystical interpretation seems to have been a consequence of rather than

a stimulus to investigation. An old Egyptian treatise reads (Cantor, p.

63): "I hold the wooden pin (Nebi) and the handle of the mallet (semes),

I hold the line in concurrence with the Goddess S[a.]fech. My glance

follows the course of the stars. When my eye comes to the constellation

of the great bear and the time of the number of the hour determined by

me is fulfilled, I place the corner of the temple." This incantation

method could hardly advance intelligence; but the methods of practical

measuring were more effective. Here the rather happy device of using

knotted cords, carried about by the Harpedonapts, or cord stretchers,

was of some moment. Especially, the fact that the lengths 3, 4, and 5,

brought into triangular form, served for an interesting connection

between arithmetic and the right triangle, was not a little gain, later

making possible the discovery of the Pythagorean theorem, although in

Egypt the theoretical properties of the triangle were never developed.

The triangle obviously must have been practically considered by the

decorators of the temple and its builders, but the cord stretchers

rendered clear its arithmetical significance. However, Ahmes' "Rules for

attaining the knowledge of all dark things ... all secrets that are

contained in objects" (Cantor, _loc. cit._, p. 22) contains merely a

mixture of all sorts of mathematical information of a practical

nature,--"rules for making a round fruit house," "rules for measuring

fields," "rules for making an ornament," etc., but hardly a word of

arithmetical and geometrical processes in themselves, unless it be

certain devices for writing fractions and the like.

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