本书内容如下为例：

1 Individual decision
In economics, it is traditionally assumed that an agent’s behavior can be
broken down into a series of parallel or sequential actions, chosen as the
result of a process of mental deliberation. The agent thus appears as an
autonomous decision-maker who chooses, either consciously or implicitly,
in a situation that can be isolated from its context, between the various alternatives
presented to him. Furthermore, this decision-making process is
assumed to be rational, by virtue of two remarkable properties. Firstly, the
agent is “consequentialist” in the sense that he chooses his action solely
according to its (foreseeable) consequences; secondly, he is “utilitarian” in
the sense that he evaluates the effects of his action by weighing up its costs
and advantages. Consequently, such an agent is restricted to a minimal
psychological framework, insofar as his choices are governed exclusively
by three personal choice determiners: his opportunities (delimiting the
space of his possible actions), his representations (enabling him to predict
the consequences of his action) and his preferences (inducing a
judgment on these consequences). These three determiners are further
combined in a choice rule which characterizes more precisely the rationality
of the decision-maker.
In the classical approach, the decision-maker is animated by very strong
rationality relying on three assumptions. First, given his prior beliefs, he is
capable of perfectly anticipating the effects of his actions. Second, he
judges his actions on the basis of one unique synthetic criterion, utility,
which sums up their costs and advantages. Third, he adopts optimising behaviour,
in the sense that he seeks the action that maximises his utility (defined
directly on the actions beyond their effects) under certain constraints
(those limiting the set of his possible actions). These assumptions have
been progressively weakened, but only to a limited degree. When dropping
the first assumption, the decision-maker only possesses imperfect information
about his environment. The more complex modification of the second
assumption gives us a decision maker using multiple, but nevertheless
commensurable, criteria of choice. The third assumption is generally kept
and assumes that the decision-maker makes his choice without having any
real difficulty in calculating what his optimum action is.