Drawing Movements as an Outcome of the Principle of Least Action

According to the two-thirds power law the cube of the speed of a drawing movement is proportional to the radius of curvature of the trajectory, and the coefficient of proportionality has the meaning of mechanical power. We derive this empirical law from the variational principle known in physics as the principle of least action. It states that if a movement between two points of a given path obeys the two-thirds law, then the amount of work required to execute a trajectory in a fixed time is minimal. In this strict sense one may say that among infinitely many ways to execute a given path, the central nervous system chooses the most economical. We show that the kinematic equations for all drawing movements are solutions of a certain differential equation with a single (time-variable) coefficient. We consider several special cases of drawing movements corresponding to simplest forms of this coefficient. Copyright 2001 Academic Press.     

The semantic side of decision making

The research reported in this paper follows the perspective that decision making is a meaningful act that conveys information. Furthermore, the potential meanings associated with decision options may affect the decisions themselves. This idea is examined in the contexts of compensation, donation, and exchange. In general, judgments were relation dependent and meaning dependent. Furthermore, the results show nonmonotonicities and limited substitutability in a pattern that challenges straightforward ways of mapping decisions onto a common currency of utility.     

Loss of coherency of the alpha/beta interface boundary in titanium alloys during deformation

The loss of coherency of interphase boundaries in two-phase titanium alloys during deformation was analyzed. The energy of the undeformed interphase boundary was first determined by means of the van der Merwe model for stepped interfaces. The subsequent loss of coherency was ascribed to the increase of interphase energy due to absorption of lattice dislocations and was quantified by a relation similar to the Read–Shockley equation for low-angle boundaries in single-phase alloys. It was found that interphase boundaries lose their coherency by a strain of approximately 0.5 at T = 800°C.     

Wittgenstein Studies and Contemporary Pyrrhonism

Interpretation of Wittgenstein’s statement ‘whereof one cannot speak, thereof one must be silent’ and consequences of rule-following paradox is the topic of this article. The revision of Wittgensteinian approach to the relations between speech and mind, and approaches to the speech by Vygotsky and Austin allow approving the disagreement with Wittgenstein and exhibit the cases when is necessary ‘to break silence and speak’. Argument is based on the hermeneutical approach to the skeptical image of Wittgenstein studies that disclose the meaning of hypothetic relevance between performative utterances and impulses generated by inner speech. Wittgenstein’s ideas are demonstrated as the contemporary version of a Pyrrhonism. Classical skepticism intensifies procedures for justification of philosophical knowledge, because philosophy tries to disprove skeptical claims. Wittgenstein studies play approximately the same role. Interpretation of the proposition ‘whereof one cannot speak, thereof one must be silent’ in a view of performative utterance allow coordinating the inner philosophical speech made by Wittgenstein, and the speech made by his commentators and critics.     

A General Framework for $$ {FDE}$$ FDE -Based Modal Logics

We develop a general theory of FDE-based modal logics. Our framework takes into account the four-valued nature of FDE by considering four partially defined modal operators corresponding to conditions for verifying and falsifying modal necessity and possibility operators. The theory comes with a uniform characterization for all obtained systems in terms of FDE-style formula-formula sequents. We also develop some correspondence theory and show how Hilbert-style axiom systems can be obtained in appropriate cases. Finally, we outline how different systems from the literature can be expressed in our framework.

     

Induction as conditional probability judgment

Existing research on category-based induction has primarily focused on reasoning about blank properties, or predicates that are designed to elicit little prior knowledge. Here, we address reasoning about nonblank properties. We introduce a model of conditional probability that assumes that the conclusion prior probability is revised to the extent warranted by the evidence in the premise. The degree of revision is a function of the relevance of the premise category to the conclusion and the informativeness of the premise statement. An algebraic formulation with no free parameters accurately predicted conditional probabilities for single- and two-premise conditionals (Experiments 1 and 3), as well as problems involving negative evidence (Experiment 2).     

Out of sorts? Some remedies for theories of object concepts: a reply to Rhemtulla and Xu (2007)

Responds to comments made by Rhemtulla and Xu on the current authors' original paper Concepts of individual objects (e.g., a favorite chair or pet) include knowledge that allows people to identify these objects, sometimes after long stretches of time. In an earlier article, the authors set out experimental findings and mathematical modeling to support the view that judgments of identity depend on people's beliefs about the causal connections that unite an object's earlier and later stages. This article examines M. Rhemtulla and F. Xu's (2007) critique of the causal theory. The authors argue that M. Rhemtulla and F. Xu's alternative sortal proposal is not a necessary part of identity judgments, is internally inconsistent, leads to conflicts with current theories of categories, and encounters problems explaining empirical dissociations. Previous evidence also suggests that causal factors dominate spatio-temporal continuity and perceptual similarity in direct tests. The authors conclude that the causal theory provides the only existing account consistent with current evidence. (PsycINFO Database Record (c) 2007 APA, all rights reserved).     

Belief in a zero-sum game and subjective well-being across 35 countries

Current Psychology - This article presents a short research report on the relationship between perceived antagonism in social relations measured using the Belief in a Zero-Sum Game (BZSG) scale,...