SEMAINE D ETUDE SUR LE ROLE DE LANALYSE ECONOMETRIOUE ETC.

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consumers had infinite opportunities of trial and error, they
must now know their preferences perfectly. The second postulate
 thereby reduces to the first).
This is enough for our purposes. To synthesize these results
 for the following analysis, we may simply state them in
three propositions:

a) at each level of per-capita income, the proportion of income
 spent on any commodity is generally verv different
from one commodity to another:

h) as per-capita real income increases, each increment of demand
 tends to concentrate on a particular group of commodities.
 This group of commodities changes from one level
of income to another (it may be mainly food at very low
levels of income, clothes and again food at slightly higher
levels of income, houses, durables and services of various
kinds at further higher levels, etc.). In other words, as
.ncome increases, the tendency of the consumers is not to
.ncrease proportionally the consumption of already-bought
commodities, but rather to buy new goods and services or
also to satisfy old needs with different (better) goods:

~)
AW

there is no commodity for which any individual’s consumption
 can be increased indefinitely. An upper saturation level
exists for all types of goods and services, although at different
 levels of income: it may be reached sharply — in the
case of goods satisfying physiological needs — or only
through a slow and long process as income increases — in
the case of services yielding very sophisticated types of
satisfaction — but its attainment is eventually inevitable.
Moreover, demand for some particular goods (inferior goods)
may in fact decrease, after reaching saturation, if real income
 persistently goes on growing.

If we want to represent these results graphically, by plotdng
 the expenditure for each commodity as a function of real

10] Pasinetti - pag. 65