In studying cognition, we infer the presence of mental structures in an idealized setting from performance in various experimental settings. Although experimental settings are believed to tap the mental structure of interest, they also always reflect idiosyncratic task-pecific properties. Indeed, distinct methods often diverge in their outcomes. How can we assess the presence of the mental structure in the idealized setting given divergent outcomes of distinct methods? We illustrate this problem in a specific example concerning the contribution of phonology in reading. Evidence for the role of phonology in the "idealized" reading setting is assessed by different methods. Methods of masked and unmasked display disagree in their outcomes. The contribution of phonology appears robust under masking, but limited under unmasked display. We outline two alternative explanations for the robustness of phonological effects under masking. On one view, phonemic masking effects are a true reflection of early reading stages (Berent & Perfetti, 1995). Conversely, Verstaen et al. (1995) argue (1) that masking overestimates the contribution of phonology and (2) that phonemic masking effects are eliminated by a manipulation that discourages reliance on phonology. We demonstrate that (2) is incorrect, but (1) cannot be resolved empirically.