and a few quotations
It is true, or course, that theories do not solve problems in the world; people do. Nevertheless, good theory is what we need when we get stuck. Theories can help alert us to problems, point us toward strategies of response, remind us of what we care about, or prompt our practical insights into the particular cases we confront (Forester 1989:ref 12).
Bohm (1987) calls what focuses looking "theory." In his sense of the term, theory determines what is "lifted to attention" or "relevated" or "made relevant" (p. 151). Thus, the pattern does not preexist the looking but literally emerges in the act of looking (Oberg 2004: 244 #10).
Theories are not facts... Theories are what make it possible to transfer a large number of factual observations into a logical system of ideas that explains the real world in a coherent and understandable fashion (McClendon 1995: 145).
[A theory is] a coherent system of rules and principles, a more or less verified or established explanation accounting for known facts or phenomena (Gell Mann 1995: 90)....
[Never thought I would have occasion to quote the Pope, but in reading a message citing consistency betweenevolution and Christianity, the following comments seemed well put.] What is the significance of such a theory? To address this question is to enter the field of epistemology. A theory is a metascientific elaboration, distinct from the results of observation but consistent with them. By means of it a series of independent data and facts can be related and interpreted in a unified explanation. A theory's validity depends on whether or not it can be verified, it is constantly tested against the facts; wherever it can no longer explain the latter, it shows its limitations and unsuitability. It must then be rethought.[T2] In a broad sense, theories can be conceived as the conceptual schemas we apply to draw relations among our perceptions of the world in a way that allows us to explain and understand the manifestation of these perceptions. In addition, and perhaps most specifically, theories allow us to project future manifestations. This broad conception expands 'theory' beyond the purview of 'theorists', suggesting that it is the purview of each of us: We each carry theories - explicitly or implicitly - that guide our understandings and actions.
Furthermore, while the formulation of a theory like that of evolution complies with the need for consistency with the observed data, it borrows certain notions from natural philosophy. And, to tell the truth, rather than the theory of evolution, we should speak of several theories of evolution. On the one hand, this plurality has to do with the different explanations advanced for the mechanism of evolution, and on the other, with the various philosophies on which it is based. Hence the existence of materialist, reduc tionist and spiritualist interpretations. What is to be decided here is the true role of philosophy and, beyond it, of theology (Pope John Paul II 1996).
[T3] More specific conceptions of theory (generally found in the 'harder' sciences) require 'predictions' (not just 'projections') of future manifestations: Only conceptual schema that can reliably and accurrately predict outcomes can be termed 'theories'. Otherwise they are merely hypotheses or conjectures.
[T4] By the latter specific definition of theory, there is no theoretical discussion in this dissertation. By the broad definition, there is a considerable amount. Since I include theory' as one of the main threads, I indicate my reliance on the broader understanding.

2003 - 2007