SEMAINE D'ÉTUDE SUR LE ROLE DE L’ANALYSE ECONOMETRIQUE ETC. 129. 
are these systems “in the air” today, but I think they will continue 
to be so, I even think they will constitute the main object of our 
discussion in the future. If we are discussing the econometrics of the 
future we have to recognise this, and I will state a personal belief 
that 100 years from now our grand-children will devote practically 
all their efforts to the study of those models that deviate from the 
free market system. They will use only an infinitesimal amount of 
their energy discussing such things as, say, the stability of the 
2quilibrium in a free market system. This is my conception of the 
>conometrics of the future. A second point that was raised by Prof 
ALLAIS was regarding social preferences. He objected to these prefe- 
rences being decided by the responsable political authority. To this 
{ can simply answer that so far there has not been invented any other 
machinery than the political one, for steering an economy. We have 
‘© accept this as a basic datum in our scientific researches. 
The purpose of this conference is not to go into a complete 
discussion of political theory and describe the whole list of political 
system that are conceivable. But some political system there must 
de and some authority has fo decide in the end. This I take as my 
starting point. I simply accept the existence of a political authority 
vhatever its nature may be. 
A third point mentioned by Prof. Arrais: Who can decide on 
vhat magnitudes ought to be attributed to the variables? The 
politician cannot do it because he does not know econometrics. The 
answer to this question hinges upon the distinction between the gross 
ind the net form of the preference function. Of course the politician 
does not know the depth of econometrics. This is precisely why the 
scientific analyst in his interview with the policy maker has to con- 
centrate on the gross form of the preference function, on the « Santa 
Claus » form of the preference function. From the purely 
psychological point of view you may, of course, interpret the word 
gross as anything under the sun. But this is not what I have done. 
l have put up a well-defined model, I have defined my concept of 
gross and net. So therefore I must say that I find Prof. ALLAIS 
remark in this particular connection absolutely irrelevant to the di 
scussion of mv paner. 
17) Frisch - pag. 25