However, at higher concentrations, MPH produces nonexocytotic dopamine release, which is the sine qua non effect of releasers.
Menzies (1989, 1996) discusses examples involving causal pre-emption where non-causes raise the probabilities of non-effects.
The challenge, then, is to find a way to capture the non-effects of actions more succinctly in formal logic.
The additional models show the same non-effects, which again leads to the conclusion that we cannot demonstrate the 'migration effect'.
The procedure proposed involves a four-parameter logistic dose-response model, which allows incorporating spontaneous effects as well as non-effects due to an insusceptible subpopulation.
This is the question of how to compute the consequences of an action without the computation having to range over the action's non-effects.
In contrast to the AI researcher's problem, the philosopher's question isn't expressed in the context of formal logic, and doesn't specifically concern the non-effects of actions.
Crucially, we have to find a way to deal with the non-effects of actions; this is the famous frame problem.
To most AI researchers, the frame problem is the challenge of representing the effects of action in logic without having to represent explicitly a large number of intuitively obvious non-effects.
For instance, given an action, think about what changes if the action is performed and what does not generally the latter is much more difficult to produce than the former, leading to large, complex attempts to specify the non-effects.
Although this problem has been generalized by philosophers such as Dennett (1984) to a general problem of relevance and salience of properties pertaining to action, the heart of the problem is that in a 'common-sense' setting as one encounters in AI, it is virtually impossible to specify all the effects by the actions of concern, as well as, notably, all non-effects.
