Footprint 37 asks if it is actually possible, useful, or even necessary to appraise theories of architecture. The articles and reviews included in the issue examine the potential purpose such appraisal might have, who should do it, and when should it take place. According to the issue contributors, appraisal can consist in analysing and classifying theories accordant with their epistemological and/or pragmatic orientation. Some theories will inevitably incorporate substantial portions of tacit knowledge, either because they are deliberately shielded from criticism or because they contain practical know-how that simply hasn't found adequate means for systematic conceptualization. Consequently, the pragmatist assumption that the quality of a theory can be measured in relation to its practical effects should also account for unforeseeable effects and generative potential. Furthermore, we are reminded that every act of appraisal is often accompanied by feelings of apprehension, and that it is always possible to alleviate those feelings by diffusing, relativising, and thus relaxing
