Leibniz frequently argued that reasons are to be weighed against each other as in a pair of scales, as Professor Marcelo Dascal has shown in his article "The Balance of Reason." In this kind of weighing it is not necessary to reach demonstrative certainty – one need only judge whether the reasons weigh more on behalf of one or the other option However, a different kind of account about rational decision-making can be found in some of Leibniz's writings. In his (...) article "Was Leibniz's Deity an Akrates?" Professor Jaakko Hintikka has argued that Leibniz developed a new vectorial model for rational decisions which is better suited to complicated decisions, where values are complementary to each other. This model, related closely to his work in metaphysics and the philosophy of mind, is a heuristic device which helps in finding rational combinations - and in an ideal case an optimum - between plural inclinations to the good. I shall argue that Leibniz applies more or less implicitly both of these models in his practical rationality. In simple situations he applied the pair of scales model and in more complicated situations he applied the vectorial model. (shrink)

Conceptual integration theory (Fauconnier & Turner, 1998, 2002) is re-examined in the light of recent criticisms (e.g., Gibbs, 2000, 2001). It is argued that the assumption of four independent "cognitive spaces" enters the model primarily as an entailment of the "space," "blending," and "construction" metaphors, leads to unnecessary ambiguity, and works against statement of the theory in a form that supports derivation of testable hypotheses. Several examples from Fauconnier and Turner (2002) are analyzed to show that they can be interpreted (...) more simply, without need of four separate "spaces." Suggestions are made for reformulating conceptual integration theory without the problematic metaphors. (shrink)