Screening-off and Causal Completeness
Elliott Sober, Hans Reichenbach Professor and William F. Vilas Research Professor, Department of Philosophy, University of Wisconsin, Madison
Here are two principles about causation that involve the ideas of screening-off and causal completeness:
(IL) In a causal chain from C to I to E, the intermediate link I will screen-off C from E if I is causally complete.
(CC) Where C is the common cause of E1 and E2, C will screen-off E1 from E2 if C is causally complete.
In this talk I’ll clarify each of these principles and then consider what happens to screening-off when the causes one considers are not causally complete. The main result I’ll discuss is the following “no-go theorem” : in a rather general setting, if the composite cause C1&C2&…&Cn screens-off one event from another, then each of the n component causes C1, C2, …, Cn must fail to screen-off.
Sober is the author of Evidence and Evolution: The Logic Behind the Science (Cambridge University Press).
Cosponsored by the Department of Philosophy and the History and Philosophy of Science Graduate Program