It is often claimed that there can be no such thing as a logic of scientific discovery, but only a logic of verification. By ‘logic of discovery’ is usually meant a normative theory of discovery processes. The claim that such a normative theory is impossible is shown to be incorrect; and two examples are provided of domains where formal processes of varying efficacy for discovering lawfulness can be constructed and compared. The analysis shows how one can treat operationally and formally phenomena that have usually been dismissed with fuzzy labels like ‘intuition’ and ‘creativity’.

The measurement of force is based on a formal law of additivity, which characterizes the effects of two or more configurations on the equilibrium of a material point. The representing vectors (resultant forces) are additive over configurations. The existence of a tight interrelation between the force vector and the geometric space, in which motion is described, depends on observations of partial (directional) equilibria; an axiomatization of this interrelation yields a proof of part two of Newton's second law of motion.

The present results (which were derived from a curious and deep isomorphism between force measurement and trichromatic color measurement) yield a kind of subunit, which needs to be incorporated into more complete axiomatizations of mechanics that would fulfill the Mach–Kirchhoff program.

We consider the mind-dependence or independence of the “now,” of “becoming,” and of “time's arrow,” by considering the various senses in which these notions might be mind-dependent or not. These matters cannot be sensibly discussed without taking a stand regarding criteria of “reality.” Proceeding from a basically phenomenalist position we conclude that merely to differentiate between appearance and reality is implicitly to assume a directed flow of time. We discuss the relationship between phenomenological and physical time and their possible asymmetries. We find that physical time acquires meaning only through phenomenological time, and that phenomenological time is fundamentally asymmetric. This still leaves room for the question: Is there anything in physical time which reflects the fact that it, to be meaningful, must be applied asymmetrically? The relevance of relativity theory to this question is discussed.

Many philosophers have asserted that evolutionary theory is unfalsifiable. In this paper I refute these assertions by detailing some falsifiable predictions of the theory and the evidence used to test them. I then analyze both these predictions and evidence cited to support assertions of unfalsifiability in order to show both what type of predictions are possible and why it has been so difficult to spot them. The conclusion is that the apparent logical peculiarity of evolutionary theory is not a property of evolutionary theory; it is a property of our human-sized perspective on evolutionary theory.