Ethics and welfare economics -- Cardinal utility in welfare economics and in the theory of risk-taking -- Cardinal welfare, individualistic ethics, and interpersonal comparisons of utility -- Ethics in terms of hypothetical imperatives -- Can the maximin principle serve as a basis for moraltiy? A critique of John Rawl's theory -- Nonlinear social welfare functions : Do welfare economists have a special examption from Bayesian rationaltiy? -- Rational-choice and game theoretical models of social behavior -- Advances in understanding rational behavior -- Rational-choice models of political behavior vs. functionalist and conformist theories -- Game theory and the analysis of international conflicts -- Measurement of social power, opportunity costs, and the theory of two-person bargaining games -- Measurement of social power in n-person reciprocal power situations -- A bargainiing model for social status in informal groups and formal organizations -- Scientific explanation -- Explanation and comparative dynamics in social science -- popper's improbability criterion for the choice of scientific hypotheses.