A series of experiments conducted in Japan by Yamagishi and his associates are presented, all consistently showing that high trusters (as measured with a general trust scale) are more sensitive than low trusters to information potentially revealing lack of trustworthiness in others and judge other people's choice in a one‐shot prisoner's dilemma more accurately. Based on these findings, a new theoretical twist is introduced to the “emancipation theory of trust” originally proposed by Yamagishi & Yamagishi (1994), that emphasizes the relation‐expansion role of trust in addition to the traditionally noticed relation‐fortification role of trust. When opportunity cost for staying in a commitment relation is generally high, it is more advantageous not to stay in secure and stable commitment relations but to explore opportunities that lie outside, and yet such social exploration involves the risk of being exploited by untrustworthy people. It is thus a more gainful strategy to invest “cognitive resources” in the nurturing of “social intelligence” needed to detect signals of untrustworthiness. General trust may be conceived as a by‐product of the development of such social intelligence. Those who have invested in the development of social intelligence can afford to maintain a high level of general trust, whereas those who have not are encouraged to assume that “everyone is a thief” and to refrain from pursuing potentially lucrative but risky outside opportunities.

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The interlayer Josephson coupling in the vortex fluid phase of heavy-ion irradiated Bi 2 Sr 2 CaCu 2 O 81d is probed by Josephson plasma resonance. The introduction of columnar defects changes the nature of the vortex liquid dramatically. We show that two types of vortex liquid, the well-coupled and the decoupled pancake vortex liquids, appear in the irradiated crystals. The pancake vortices tend to couple with increasing magnetic field, which is opposite to the pristine crystal. The double resonance peaks appear as a function of field in a narrow temperature range well above the irreversibility line. This implies an occurrence of the coupling transition in the liquid phase. [S0031-9007(97)04422-0] PACS numbers: 74.60. Ge, 72.30. + q, 74.25.Nf, 74.72.Hs The nature of the flux-line structure and the phase transition between different vortex states have become central issues in the study of the physics of the vortex state of superconductors. In high-T c superconductors (HTSC), strong thermal fluctuations result in a noticeable change in the nature of the vortex state [1]. In sufficiently clean crystals, the vortex solid melts into a liquid through a first-order-phase transition (FOPT), which has been recently confirmed by thermodynamic measurements of Bi 2 Sr 2 CaCu 2 O 81d [2] and YBa 2 Cu 3 O 7-d [3]. Moreover, several experiments have revealed that the loss of long range out-of-plane correlation of the pancake vortices occurs simultaneously at FOPT [4]. Particularly, in Bi 2 Sr 2 CaCu 2 O 81d with extremely large anisotropy, it has been demonstrated that at FOPT the vortex lattice also dissociates into a decoupled pancake liquid in which even short range out-of-plane correlation becomes negligible [5]. Accordingly, almost the entire regime of the liquid phase in Bi 2 Sr 2 CaCu 2 O 81d is well described by the concept of the decoupled pancake. On the other hand, it is well established that the introduction of columnar defects (CDs) by the heavy-ion irradiation causes a dramatic enhancement of the out-of-plane correlation of pancake vortices. The introduction of CDs results in the appearance of a second-order Bose-glass (BG) transition line which is shifted to a significantly higher field compared to FOPT of the pristine material [6]. However, despite the fact that there is much experimental evidence to support this BG transition [7], the nature of the vortex liquid above the transition remains unclear. Transport measurements on irradiated Bi 2 Sr 2 CaCu 2 O 81d imply that the vortex may move as a linear object rather than as a decoupled pancake [8]. On the other hand, magnetization measurements in the liquid phase suggest that the decoupled pancakes are placed randomly within CDs at low fields [9]. The question is, then, how does the well-coupled liquid dissociate into the liquid of the decoupled pancake with B and T? There are no explicit predictions, nor has there been any detailed experimental investigations of the out-of-plane correlation in the liquid phase of HTSC with CDs.To understand the nature of the...