evidential decision theory computes an act’s expected utility using the probability
of a state given the act P(S|A)
10 ; in the second case, causal decision theory replaces
P(S|A) with P(A ! S) or a similar causal probability [24]. This choice defines the
decision making perspective. Thus, according to Jeffrey, “in decision-making it is
deliberation, not observation, that changes your probabilities. To think you face a
decision problem rather than a question of fact about the rest of nature is to expect
whatever changes arise in your probabilities for those states of nature during your
deliberation to stem from changes in your probabilities of choosing options” [25].
Rationality is therefore at least dual, and Lewis’s counterfactual decision theory
can account for both aspects [26]. The fundamental idea of this analysis is that the
counterfactual “If A were the case, C would be the case” is true just in case it takes
less of a departure from actuality to make the antecedent true along with the
consequent than to make the antecedent true without the consequent [27]. The
causal dependence is then stated as follows: Where c and e are two distinct actual
events, e causally depends on c if and only if, if c were not to occur, e would not
occur.
A dual rationality goes hand-in-hand with the concept of temporality. Either the
decision maker operates by projecting a set of possible futures and seeks to maximize the consequences of their actions, or they try to make their actions as consistent as possible with a desirable state of the world. Dupuy [28] thus states that:
either, at every moment in ‘occurring time’, regardless of the predictions of an
infallible Predictor, “agents have the power to act in such a way that, if they were so
to act, they would render inaccurate the predictions of the supposed Predictor”,
which means that causal links are probable ones; or, at all times in ‘projected time’,
causal links are fixed and the agent has the power to do something such that, if he
were to do it, the ‘script’ of his life would have been different. Dupuy suggested
merging these two concepts of temporality form a loop, in which the past and the
future determine each other. In particular, a future state, when represented by a
favourable probability and another that is disastrous (with a very low probability)
can serve as an anchor point for ongoing action in an approach that is constantly
under review [26].
We argue that Yoshida was guided by these two representations of temporality.
He applied a causal type of reasoning in order to deduce from the information at his
disposal that the core of Reactor 1 was undergoing fusion. He expected to find
proof of an ‘event e’, for which it was then necessary to find the cause. Using the
same reasoning (this time in anticipation) he decided to start the venting manoeuvre
and avoid an explosion, based on the objective data available to him. Given the
information at his disposal, he assessed the plausibility of a causal link to unwanted
consequences, based on an appreciation of the law of physics. At the same time, he
organized actions to be taken based on information that he did not yet have in a
measurable form, but which he had nevertheless convinced himself was true.
10
This theoretical orientation has led to debate about the ability of an agent to assess the likelihood
of their actions—a problem that is resolved by invoking the predisposition of the agent to act [23].
176
S. Travadel
of a state given the act P(S|A)
10 ; in the second case, causal decision theory replaces
P(S|A) with P(A ! S) or a similar causal probability [24]. This choice defines the
decision making perspective. Thus, according to Jeffrey, “in decision-making it is
deliberation, not observation, that changes your probabilities. To think you face a
decision problem rather than a question of fact about the rest of nature is to expect
whatever changes arise in your probabilities for those states of nature during your
deliberation to stem from changes in your probabilities of choosing options” [25].
Rationality is therefore at least dual, and Lewis’s counterfactual decision theory
can account for both aspects [26]. The fundamental idea of this analysis is that the
counterfactual “If A were the case, C would be the case” is true just in case it takes
less of a departure from actuality to make the antecedent true along with the
consequent than to make the antecedent true without the consequent [27]. The
causal dependence is then stated as follows: Where c and e are two distinct actual
events, e causally depends on c if and only if, if c were not to occur, e would not
occur.
A dual rationality goes hand-in-hand with the concept of temporality. Either the
decision maker operates by projecting a set of possible futures and seeks to maximize the consequences of their actions, or they try to make their actions as consistent as possible with a desirable state of the world. Dupuy [28] thus states that:
either, at every moment in ‘occurring time’, regardless of the predictions of an
infallible Predictor, “agents have the power to act in such a way that, if they were so
to act, they would render inaccurate the predictions of the supposed Predictor”,
which means that causal links are probable ones; or, at all times in ‘projected time’,
causal links are fixed and the agent has the power to do something such that, if he
were to do it, the ‘script’ of his life would have been different. Dupuy suggested
merging these two concepts of temporality form a loop, in which the past and the
future determine each other. In particular, a future state, when represented by a
favourable probability and another that is disastrous (with a very low probability)
can serve as an anchor point for ongoing action in an approach that is constantly
under review [26].
We argue that Yoshida was guided by these two representations of temporality.
He applied a causal type of reasoning in order to deduce from the information at his
disposal that the core of Reactor 1 was undergoing fusion. He expected to find
proof of an ‘event e’, for which it was then necessary to find the cause. Using the
same reasoning (this time in anticipation) he decided to start the venting manoeuvre
and avoid an explosion, based on the objective data available to him. Given the
information at his disposal, he assessed the plausibility of a causal link to unwanted
consequences, based on an appreciation of the law of physics. At the same time, he
organized actions to be taken based on information that he did not yet have in a
measurable form, but which he had nevertheless convinced himself was true.
10
This theoretical orientation has led to debate about the ability of an agent to assess the likelihood
of their actions—a problem that is resolved by invoking the predisposition of the agent to act [23].
176
S. Travadel