There are more stems per item in Athabascan , which expresses the fact that the Athabascan languages have undergone somewhat more change in diverging from proto-Athabascan than the Yokuts languages from proto-Yokuts .
This may be because the Athabascan divergence began earlier ; ;
or again because the Athabascan languages spread over a very much larger territory ( including three wholly separated areas ) ; ;
or both .
The differentiation , however , is not very much greater , as shown by the fact that Athabascan shows 3.46 stems per meaning slot as against 2.75 for Yokuts , with a slightly greater number of languages represented in our sample : 24 as against 21 .
( On deduction of one-eighth from 3.46 , the stem  item rate becomes 3.03 against 2.75 in equivalent number of languages .
) These general facts are mentioned to make clear that the total situation in the two families is similar enough to warrant comparison .


The greatest difference in the two sets of figures is due to differences in the two sets of lists used .
These differences in turn result from the fact that my Yokuts vocabularies were built up of terms selected mainly to insure unambiguity of English meaning between illiterate informants and myself , within a compact and uniform territorial area , but that Hoijer's vocabulary is based on Swadesh's second glottochronological list which aims at eliminating all items which might be culturally or geographically determined .
Swadesh in short was trying to develop a basic list that was universal ; ;
I , one that was specifically adapted to the San Joaquin Valley .
The result is that I included 70 animal names , but Swadesh only 4 ; ;
and somewhat similarly for plants , 16 as against 4 .
Swadesh , and therefore Hoijer , felt compelled to omit all terms denoting species or even genera ( ox , vulture , salmon , yellow pine , manzanita ) ; ;
their classes of animal and plant terms are restricted to generalizations or recurrent parts ( fish , bird , tree , grass , horn , tail , bark , root ) .
The groups are therefore really non-comparable in content as well as in size .


Other classes are included only by myself ( interrogatives , adverbs ) or only by Swadesh and Hoijer ( pronouns , demonstratives ) .


What we have left as reasonably comparable are four classes : ( 1 ) body parts and products , which with a proportionally nearly even representation ( 51 terms out of 253 , 25 out of 100 ) come out with nearly even ratios ; ;
2.6 and 2.7 ; ;
( 2 ) Nature ( 29 terms against 17 ) , ratios 3.3 versus 4.1 ; ;
( 3 ) adjectives ( 16 , 15 terms ) , ratios 3.9 versus 4.7 ; ;
( 4 ) verbs ( 9 , 22 terms ) , ratios 4.0 versus 3.4 .


It will be seen that where the scope is similar , the Athabascan ratios come out somewhat higher ( as indeed they ought to with a total ratio of 2.8 as against 3.5 or 4 : 5 ) except for verbs , where alone the Athabascan ratio is lower .
This exception may be connected with Hoijer's use of a much higher percentage of verbs : 22% of his total list as against 3.5% in mine .
Or the exception may be due to a particular durability peculiar to the Athabascan verb .
More word class ratios determined in more languages will no doubt ultimately answer the question .



5 .

If word classes differ in their resistance or liability to stem replacement within meaning slot , it is conceivable that individual meanings also differ with fair consistence trans-lingually .
Hoijer's Athabascan and my Yokuts share 71 identical meanings ( with allowance for several near-synonyms like stomach-belly , big-large , long-far , many-much , die-dead , say-speak ) .
For Yokuts , I tabulated these 71 items in five columns , according as they were expressed by 1 , 2 , 3 , 4 , and more than 4 stems .
The totals for these five categories are not too uneven , namely 20 , 15 , 11 , 16 , 9 respectively .
For Athabascan , with a greater range of stems , the first two of five corresponding columns were identical , 1 and 2 stems ; ;
the three others had to be spread somewhat , and are headed respectively Af ; ;
Af ; ;
and Af stems .
While the particular limits of these groupings may seem artificially arbitrary , they do fairly express a corresponding grouping of more variable material , and they eventuate also in five classes , along a similar scale , containing approximately equal numbers of cases , namely 19 , 14 , 15 , 11 , 12 in Athabascan .


When now we count the frequency of the 71 items in the two language families appearing in the same column or grade , or one column or grade apart , or two or three or four , we find these differences : Af

.
This distribution can be summarized by averaging the distance in grades apart : Af ; ;
which , divided by Af gives a mean of 1.07 grades apart .
If the distribution of the 71 items were wholly concordant in the two families , the distance would of course be 0 .
If it were wholly random and unrelated , it would be 2.0 , assuming the five classes were equal in n , which approximately they are .
The actual mean of 1.07 being about halfway between 0 of complete correlation and 2.0 of no correlation , it is evident that there is a pretty fair degree of similarity in the behavior even of particular individual items of meaning as regards long-term stem displacement .



6 .

In 1960 , David D. Thomas published Basic Vocabulary In some Mon-Khmer Languages ( AL 2 , No. 3 , pp. 7 - 11 ) , which compares 8 Mon-Khmer languages with the I-E language data on which Swadesh based the revised retention rate ( Af ) in place of original ( Af ) , and his revised 100 word basic glottochronological list in Towards Greater Accuracy ( IJAL 21 : :
121 - 137 ) .
Thomas' findings are , first , `` that the individual items vary greatly and unpredictably in their persistence '' ; ;
but , second , `` that the semantic groups are surprisingly unvarying in their average persistence '' ( as between M-K and I-E ) .
His first conclusion , on behavior of individual items , is negative , whereas mine ( on Ath. and Yok. ) was partially positive .
His second conclusion , on semantic word classes , agrees with mine .
This second conclusion , independently arrived at by independent study of material from two pairs of language families as different and remote from one another as these four are , cannot be ignored .


Thomas also presents a simple equation for deriving an index of persistence , which weights not only the number of stems ( ' roots ' ) per meaning , but their relative frequency .
Thus his persistence values for some stem frequencies per meaning are : stem identical in 8 languages , 100% ; ;
stem frequencies 7 and 1 , 86% ; ;
stem frequencies 4 and 4 , 64% ; ;
stem frequencies 4 , 3 , and 1 , 57% .
His formula will have to be weighed , may be altered or improved , and it should be tested on additional bodies of material .
But consideration of the frequency of stems per constant meaning seems to be established as having significance in comparative situations with diachronic and classificatory relevance ; ;
and Gleason presumably is on the way with a further contribution in this area .


As to relative frequencies of competing roots ( 7 - 1 vs. 4 - 4 , etc. ) , Thomas with his ' weighting ' seems to be the first to have considered the significance this might have .
The problem needs further exploration .
I was at least conscious of the distinction in my full Yokuts presentation that awaits publication , in which , in listing ' Two-Stem Meanings ' , I set off by asterisks those forms in which N of stem B was Af of stem A , the unasterisked ones standing for Af ; ;
or under ' Four Stems ' , I set off by asterisks cases where the combined N of stems Af was Af .



7 .

These findings , and others which will in time be developed , will affect the method of glottochronological inquiry .
If adjectival meanings show relatively low retentiveness of stems , as I am confident will prove to be the case in most languages of the world , why should our basic lists include 15 per cent of these unstable forms , but only 8 per cent of animals and plants which replace much more slowly ? ?
Had Hoijer substituted for his 15 adjectival slots 15 good animal and plant items , his rate of stem replacement would have been lower and the age of Athabascan language separation smaller .
And irrespective of the outcome in centuries elapsed since splitting , calculations obviously carry more concordant and comparable meaning if they deal with the most stable units than with variously unstable ones .


It is evident that Swadesh has not only had much experience with basic vocabulary in many languages but has acquired great tact and feeling for the expectable behavior of lexical items .
Why then this urge to include unstable items in his basic list ? ?
It is the urge to obtain a list as free of geographical and cultural conditioning as possible .
And why that insistence ? ?
It is the hope of attaining a list of items of universal occurrence .
But it is becoming increasingly evident that such a hope is a snare .
Not that such a list cannot be constructed ; ;
but the nearer it comes to attaining universality , the less significant will it be linguistically .
Its terms will tend to be labile or vague , and they will fit actual languages more and more badly .


The practical operational problem of lexicostatistics is the establishment of a basic list of items of meaning against which the particular forms or terms of languages can be matched as the medium of comparison .
The most important quality of the meanings is that they should be as definable as possible .
In proportion as meanings are concrete , we can better rely on their being insulated and distinctive .
An elephant or a fox or a swan or a cocopalm or a banana possess in unusually high degree this quality of obvious , common-sense , indubitable identity , as do an eye or tooth or nail .
They isolate out easily , naturally , and unambiguously from the continuum of nature and existence ; ;
and they should be given priority in the basic list as long as they continue to show these qualities .


With the universal list as his weapon , Swadesh has extended his march of conquest farther and farther into the past , eight , ten , twelve millennia back .
And he has proclaimed greater or less affiliation between all Western hemisphere languages .
Some of this may prove to be true , or even considerable of it , whether by genetic ramification or by diffusion and coalescence .
But the farther out he moves , the thinner will be his hold on conclusive evidence , and the larger the speculative component in his inferences .
He has traversed provinces and kingdoms , but he has not consolidated them behind him , nor does he control them .
He has announced results on Hokan , Penutian , Uto-Aztecan , and almost all other American families and phyla , and has diagrammed their degree of interrelation ; ;
but he has not worked out by lexicostatistics one comprehensively complete classification of even a single family other than Salish .
That is his privilege .
The remote , cloudy , possible has values of its own -- values of scope , stimulus , potential , and imagination .
But there is also a firm aspect to lexicostatistics : the aspect of learning the internal organization of obvious natural genetic groups of languages as well as their more remote and elusive external links ; ;
of classification first , with elapsed age merely a by-product ; ;
of acquiring evidential knowledge of what happened in Athabascan , in Yokuts , in Uto-Aztecan in the last few thousand years as well as forecasting what more anciently may have happened between them .
This involves step-by-step progress , and such will have to be the day-by-day work of lexicostatistics as a growing body of scientific inquiry .
If of the founders of glottochronology Swadesh has escaped our steady plodding , and Lees has repudiated his own share in the founding , that is no reason why we should swerve .



8 .

There is no apparent reason why we should feel bound by Swadesh's rules and procedure since his predilections and aims have grown so vast .
It seems time to consider a revision of operational procedures for lexicostatistic studies on a more humble , solid , and limited basis .


I would propose , first , an abandonment of attempts at a universal lexical list , as intrinsically unachievable , and operationally inadequate in proportion as it is achieved .


I would propose , next , as the prime requirement for constitution of new basic lists , items whose forms show as high an empirical retention rate as possible .
There would be no conceivable sense in going to the opposite extreme of selecting items whose forms are the most unstable .
An attempted middle course might lead to devices like a 5000-word alphabetized dictionary from which every fiftieth word was selected .

