Online research in philosophy

This book develops an explanation for the roles of observation and theory in scientific endeavor that occupies the middle ground between empiricism and rationalism, and captures the strengths of both approaches. Brown argues that philosophical theories have the same epistemological status as scientific theories and constructs an epistemological theory that provides an account of the role that theory and instruments play in scientific observation. His theory of perception yields a new analysis of objectivity that combines the traditional view of observation as the foundation of scientific objectivity with the contemporary recognition that observation is theory-dependent.

In this paper I argue for the cognitive impenetrability of perception by undermining the argument from reentrant pathways. To do that I will adduce psychological and neuropsychological evidence showing that (a) early vision processing is not affected by our knowledge about specific objects and events, and (b) that the role of the descending pathways is to enable the early-vision processing modules to participate in higher-level visual or cognitive functions. My thesis is that a part of observation, which I will call perception, is bottom-up and theory neutral. As such, perception could play the role of common ground on which a naturalized epistemology can be built and relativism avoided.

The aim of this paper is to analyze a philosophical question (neutrality vs. theory-ladenness of observation) taking into consideration the empirical results of Cognitive Psychology (theories of perception). This is an important debate because the objectivity of science is at stake. In the Philosophy of Science there are two main positions with regard to observation, those of C. Hempel and N. R. Hanson. In the Philosophy of Mind there are also two important contrasting positions, those of J. Fodor and Paul M. Churchland. I will analyze the consequences of recent theories of perception and vision developed within Cognitive Science for classical epistemological theses about observation.

Ever since work of Paul Feyerabend, Russell Hanson and Thomas Kuhn in the 1960s, the thesis of the theory-ladenness of scientific observation has attracted much attention both in the philosophy and the sociology of science. The main concern has always been epistemic. It was argued –or feared– that if scientific observations depend on prevalent theories, an objective empirical test of theories and hypotheses by independent observation and experience is impossible. This suggests that theories might appear to be well confirmed by observation, and yet it is not likely that they are largely true or empirically adequate. While some philosophers like Ian Hacking have argued that serious theory-dependence is less common than often assumed, sociologists such as David Bloor, Stephen Shapin, Karin Knorr-Cetina or Harry Collins have based their constructivist programs for the sociology of science on strong claims of theory-ladenness.

Kuhn's contribution should be viewed as posing a number of important problems, not as a full-fledged theory of the structure of science. Kuhn's alleged theory-ladenness of observations is examined as a test case in the light of Hintikka's interrogative model of inquiry. A certain superficial theory-ladenness is built into that model. Moreover, the model provides a deeper analysis of theory-ladenness via the two-levelled character of experimental science. A higher-level and a lower-level inquiry rely on different kinds of initial premises and operate with different kinds of "answers" by nature. The model also throws light on the alleged theory-ladenness of meaning.

Since the late 1950s one of the most important and influential views of post-positivist philosophy of science has been the theory-ladenness of observation. It comes in at least two forms: either as a psychological law pertaining to human perception (whether scientific or not) or as conceptual insight concerning the nature and functioning of scientific language and its meaning. According to its psychological form, perceptions of scientists, as perceptions of humans generally, are guided by prior beliefs and expectations, and perception has a peculiar holist character. In its conceptual form it maintains that scientists’ observations rest on the theories they accept and that the meaning of the observational terms involved depends upon the theoretical context in which they occur. Frequently, these two versions are combined with each other and give rise to a constructivist view of scientific knowledge (I shall use the term “constructivism” roughly in the same way as Golinski [1998, chap. 1]). According to this outlook, our experience is categorized and preconditioned by prior belief since the process of gaining knowledge through science always involves the use of concepts from some theory or other. This view can easily be strengthened to serve as the cornerstone of a constructivist and anti-empiricist account of science: The categories in terms of which we carve up our experience are not read off from the external world but follow from prior theoretical commitments.

In the writings of scientists we find claim to the effect that we can observe items such as pulsars, gravity waves, quarks, electrons, etc. An epistemological theory, originally developed by Dretske and modified by Jackson, is used to give an account of such claims and the extent to which they may be deemed correct. The theory eschews talk of the theory-ladenness of observation while giving an account of how our observation reports may evolve with growth in scientific knowledge. The theory is partially linked to Shapere's recent account of observation in science.

This paper attempts to argue for the theory-ladenness of evidence. It does so by employing and analysing an episode from the history of eighteenth century chemistry. It delineates attempts by Joseph Priestley and Antoine Lavoisier to construct entirely different kinds of evidence for and against a particular hypothesis from a set of agreed upon observations or (raw) data. Based on an augmented version of a distinction, drawn by J. Bogen and J. Woodward, between data and phenomena it is shown that the role of theoretical auxiliary assumptions is very important in constructing evidence for (or against) a theory from observation or (raw) data. In revolutionary situations, rival groups hold radically different theories and theoretical auxiliary assumptions. These are employed to construct very different evidence from the agreed upon set of observations or (raw) data. Hence, theory resolution becomes difficult. It is argued that evidence construction is a multi-layered exercise and can be disputed at any level. What counts as unproblematic observation or (raw) data at one level may become problematic at another level. The contingency of these constructions and the (un)problematic nature of evidence are shown to be partially dependent upon the scientific knowledge that the scientific community possesses.

Discussions of theory-ladenness have traditionally focused on the extent to which observations and observational language are pure, i.e. unaffected by theory, and hence can function as neutral adjudicators in theory testing. By contrast, the purity of theories and of theoretical language is never brought into question. My aim in this paper is to contest this view by arguing that theories and theoretical terms can be afflicted by observation-ladenness.

The first aim of this paper is to adduce a framework for understanding theory-ladenness of perception arguments. The second aim is to begin to assess an important cluster of theory-ladenness arguments-those that begin with some psychological phenomenon and conclude that scientific controversies are resolved without appeal to theory-neutral observations. Three of the arguments (from expectation effects, ambiguous figures, and inverting lenses) turn out to be either irrelevant to or subversive of theory-ladenness. And even if we grant the premises of the fourth argument (from the penetrability of the visual system), it will support at best a mild version of theory-ladenness.