Springer Nature is making Coronavirus research free. View research | View latest news | Sign up for updates

Truth-ratios, process, task, and knowledge


In this paper, I delineate two major problems facing reliabilist approaches in epistemology. I argue that Alvin Goodman's (1986) position fails to solve either problem. I then suggest an alternative reliabilist approach that ties truth-ratio assessments to particular, well-specified cognitive tasks. I claim that a well-specified cognitive task is an empirical hypothesis about a system that involves the specification of input and output types and nomic correlations (including statistical correlations) that underlie the system's performance. On my approach, one characterizes processes by reference to the system's dispositions across the situations consistent with the task. Characterization is best understood as revealing a strategy or a set of strategies for generating outputs from inputs relying on certain nomic correlations associated with the task.

This is a preview of subscription content, log in to check access.


  1. Braddick, O.: 1980, ‘Low-level and High-level Processes in Apparent Motion’,Vision Research 14, 519–27.

  2. Feldman, R.: 1985, ‘Reliability and Justification’,The Monist 68, 159–74.

  3. Feldman, R.: 1985a, ‘Schmitt on Reliability, Objectivity, and Justification’,Australasian Journal of Philosophy 63, 354–60.

  4. Goldman, A.: 1967, ‘A Causal Theory of Knowledge’,The Journal of Philosophy 64, 357–72.

  5. Goldman, A.: 1976, ‘Discrimination and Perceptual Knowledge’,The Journal of Philosophy 73, 771–91.

  6. Goldman, A.: 1979, ‘What is Justified Belief?’, in George Pappas (ed.),Justification and Knowledge, D. Reidel, Dordrecht, pp. 1–23.

  7. Goldman, A.: 1986,Epistemology and Cognition, Harvard University Press, Cambridge.

  8. Goldman, A.: 1988, ‘Strong and Weak Justification’,Philosophical Perspectives 2, 51–69.

  9. Pollock, J.: 1984, ‘Reliability and Justified Belief’,The Canadian Journal of Philosophy 14, 103–14.

  10. Shepard; R.: 1990,Mind Sights, New York, W. H. Freeman.

  11. Treisman, A.: 1987, ‘Features and Objects in Visual Processing’,Sciennfic American 255, 114–25.

  12. Wallis, C.: 1992, ‘Representation, Knowledge, and Structure in Computational Explanations in Cognitive Science’, Ph.D. Dissertation, University of Minnesota.

  13. Wallis, C.: 1994, ‘Lottery Arguments Against Reliabilism’, unpublished manuscript.

Download references

Author information

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Wallis, C. Truth-ratios, process, task, and knowledge. Synthese 98, 243–269 (1994).

Download citation


  • Cognitive Task
  • Statistical Correlation
  • Reliabilist Approach
  • Output Type
  • Alternative Reliabilist