March 7, 19 iS 
Land & Water 
1 1 
Food for Thought : By Charles Mercier 
1.\ a recently published little book on Education I have 
insisted on the desirability of teaching; children to think, 
and to think clearly, and have indicated the way in 
which this can be done. Such a startling and heretical 
doctrine naturally excited the ire of schooln^asters, and 
perhaps was not presented in a manner calculated to soothe 
them ; but there is, after all, something to be said for it, and 
evidence in its favour is furnished by a controversy on pig- 
breeding that has been recently carried on in The Times, and 
has ^spread thence to The British Medical Jounial. 
The controversy is as to whether pig-breeding is or is not 
desirable in the present circumstances of shortage of food, 
and of destruction of food ships by the (ierman submarines. 
And the arguments are as follows : 
A Committee of the Royal Society has proclaimed that to 
keep the average man in active work, the minimum daily 
ration necessary is protein loo grammes (3J oz.), fat 100 
grammes (3J oz.), and carbohydrates 500 grammes (rather 
more than i lb.). The allowance of meat prescribed by the 
['ood Controller is suthcient, when supplemented by the 
protein in pulses, beans, and cereals, to provide the necessary 
minimum of protein. The pulses and cereals, of which there 
is no serious shortage at present, furnish the carbohydrates 
(starch and sugar), but there is a deficiency iii fat, an ingre- 
dient the want of which is felt acutely. The problem is, how 
are we to provide the necessary fat ? 
The answer of Mr. C. B. Fisher is, " Breed pigs, for pig- 
breeding is the quickest and most profitable way of producing 
fats." To this the Royal Society's Committee answers, " Breed 
no pigs, for pigs consume 7 lb. of barley meal in producing 
I lb. of fat, and this is wasteful. I'^ar better let us human 
beings consume the 7 lb. of barley meal than give it to pigs 
and get only i lb. of fat in return. If we give the barley meal 
to pigs, we are wasting 61b. of food out of every seven. 
Shocking !" 
'~ The answer seems conclusive enough — if we do not think. 
But a little clear thinking, such as the Committee of the Royal 
Society omitted to bestow upon it, puts a different complexion 
on the matter. What we are short of is not cereals, of which 
barley is one, but fats ; and though pigs can easily turn 7 lb. 
of barley meal into i lb. of fat, it does not follow that fmman 
beings can do so. For a pig, 7 lb. of barley meal is equivalent 
to I lb. of fat, but they are not necessarily equivalent for a 
man, and for some men they are certainly not equivalent. 
Common observation shows that men differ very widely indeed 
in their capability of transforming food into fat. Some men 
grow fat on a very mf)derate diet ; others could not transform 
a cwt. of barley meal into i lb. of fa,t ; and if they could, they 
would have to do for themselves, ar a certain cost of energy, 
what the pig does for them at a much less cost of energy. In 
short, the pig cooks our barley meal into fat for us ; and if we 
consume the barley meal ourselves, we must do our own 
, cooking ; and some of us have no skill in this kind of cooking, 
and cannot cook the barley meal into fat ; and even those who 
do possess the skill still have to do the cooking, and so 
expend energy that might be more usefully employed. 
What a man wants is not barley meal that he can turn into 
fat, but fat itself, ready made ; and when he is eating his 7 
lb. of barley meal, he is not eating 1 lb-, of fat ; he is eating 
only 2 oz. of fat, for that is all the fat that 7 lb. of barley meal- 
contains. The rest of the fat needed he must make for himself ; 
and if it is wasteful for the pig to turn 7 lb. of barley meal into 
I lb. of fat, is it not equally wasteful for a man to t,urn 7 lb. of 
meal into less than i lb. of fat ? It is true he would be putting 
some f)f the meal, which is m(jstly carbohydrate, to other 
uses to which carbohydrates are put ; but this is not to tiie 
point. The p6int is that his ration is deficient in fat, not as yet 
in carbohydrates ; and Whatever meal is used as carbo- 
hydrate cannot go to the formation of fat, so that he does not 
git his pound of fat out of his 7 lb. of mejl. 
So far, it seems that the Committee of the Royal Society 
has not thought very clearly. We want a pound of fat ; 
and the Committee gives us 7 lb. of barley meal, and savs 
we ought to be content. Cooks — English cooks, at any 
rate — are wa.steful ; and English pigs resemble other English 
cooks in this matter, and waste six out of eyery seven pounds 
of food that is entrusted to them to cook. But there is 
another point on which a little clear thinking is necessary. 
It seems obvious that if the pigs waste six-sevenths of their 
food, men must waste at least as much ; but, after all, is the 
six-sevenths wasted ? It takes 7 lb. of meal to make i lb. 
of pcxk, or bacon, or lard. Well and good ; but what 
bercmes of the other bib. of material ? Does it vanish into 
thin air ? Some of it does, no doubt. Some of it is burnt 
up into carbonic acid and water, and after helping to sustain 
the pig's bodily temperature, is exhaled from his lungs as, 
gas. But what becomes of the remainder of the 6 lb. ? 
Is it wasted ? That depends on whether the meal is con- 
sumed 15y pigs or by men. If it is consumed bv pigs, it is 
not wasted. // i^oes to make manure, which, being applied 
to the ground, produces more cereals, some a hundredfold, 
some sixtyfold, and some thirtyfold ; but if it is consumed 
by man. it is not utilized in this way. Part of it is deposited 
in the North Sea ; other parts of it go to pollute rivers, 
streams, estuaries, and the sea round our coasts ; but little 
of it is utilised as manure, and what is so utilised goes, for 
the most part, to produce cabbages, rye-grass, and other 
crops that have not the food value of cereals. 
A farmer in my neighbourhood keeps three hundi;ed pigs, 
and after fattening them on 7 lb. of barley meal per pound 
of fat, sells them for a price that just covers the cost of 
breeding and fattening them, but yields no profit. He makes 
no profit at all out, of the sale, but it pays him well to sell 
them at cost price, for by this means he obtains large quanti- 
ties of manure, which is his profit. The manure goes to 
assist the production of various crops, among which cereals 
are conspicuous ; so that to speak of 7 lb. of barley meal 
being required to produce i lb. of fat, though it may be 
quite true, is so small a part of the truth as to be in practice 
fal.se. It is very misleading, and it misleads for want of 
clear thinking. The proper way to state the process is that 
7 lb. of barley meal produces i lb. of fat and so many pounds 
of agricultural produce ; and we want both, but it is the fat 
that is produced first. 
Professor Starling and the British Medical Journal take 
The Times to task for aspersing the fair fame of science by 
saying : " Scientific calculations about food are a very 
untrustworthy guide to practice, because the data on which 
they are based are quite inadequate to justify the conclusions 
drawn from them," but in this case it seems that The Times 
is not so very far astray. It would have been 'more accurate, 
however, if it had said, instead of "scientific calculations," 
"the calculations of men of science." As, in a humble way, 
a would-be scientific man myself, I should be the last to 
cast aspersions on science or on scientific calculations ; but 
the mischief is that the ' calculations of men devoted to 
science are not always scientific calculations. 
Professor Starling tells us, truly enough, that science is 
nothing but practical experience accurately noted, recorded, 
and classified ; and the British Medical Journal pats him 
on the back, and says, "Bravo \" But it is because science 
is nothing but practical experience that it cannot afford to 
neglect practical experience, the practical experience of the 
cook and the farmer, as well as of the physiologist. Professor 
Starling tells us, moreover, that when we are faced by an 
acute food shortage it is idle to discuss large ideals of agri- 
cultural policy. It may be, but surely it is not idle to discuss 
how best to utilise what supplies we have, which is what 
Mr. Fisher does. ' 
Mr. Fisher is a practical agriculturist, immersed in the 
practice of producing food, and accustomed, therefore, to 
take into his calculations all the data that are necessary in 
calculating the production of food. Th« highly scientific 
men, as the Committee of the Royal Society, are physiologists, 
immersed in the study of physiology, and accustomed to 
take into their calculations all the data necessary in calcu- 
lating what becomes of the food after it is eaten. But the 
problem before us concerns not only the production of food, 
but also the consumption ; and not only the consumption 
of food, but also its production ; and neither the farmer nor 
the physiologist is in a position to dogmatize on the whole 
problem. Either they should combine together and issue 
a joint report or they should both lay their evidence before 
an independent tribunal for its decision. 
I am neither farmer nor physiologist, and, so far, am 
independent ; and it seems to me that if the case is stated 
fully and clearly, as I have tried to state it, the farmer has 
the best of the argtiment ; but I do not presume to express 
a dogmatic opinion. I have shown that, for want of clear 
thinking, the men of science have omitted to consider certain 
data that vitally affect the problem. I am no expert, and 
there may be other data that I also have omitted ; but 
those I have added must be apparent to every one who 
applies his mind to the problem ; and all I wish to insist 
upon is the primary and vital necessity of clear thinking, 
e\'cn al)iiut pigs. 
