Philosophy of religion and the reality of models for modalities, 9(3), 1975, p. 393-399. The king and Y: towards a categorial grammar of being, 3(3), 1976, p. 225-243. The logical paradigm in dialectical philosophy and science, 11(1), 1977, p. 291-322. Perspectives on analytic philosophy, 42(2), 1979, p. 35-75. A new field: empirical logic', 63(3), 1985, 375-388. In the service of human society: formal, informal or anti-logical? The philosophy of the logician Evert Willem Beth (1908-1964), 12(1), 1990, p. 1-10. Argumentation: distributed or monological?, , 24(1), 1991, p. 15-24. Waiting for Godot: on attitudes towards artefacts vs. entities, as related to different phases of operation in cognition, 14, 1991, p. 77-104. Logical intention and comparative principles of empirical logic, i G. Debrock en M. Hulswit (red.), (p. 209-224), Kluwer Academic Publishers: Dordrecht 1995. A framework for intersubjective accountability: dialogical logic, i D.M. Gabbay, R.H. Johnson, H.J. Ohlbach en J. Woods (red.), (p. 225-293), Elsevier: Amsterdam 2002.