"We inevitably end up committing logical fallacies of reverse inference and faulty generalisation: that certain parts of Einstein's brain may look a bit different to other brains, and that this explains his abilities.
However, we caution against the fallacies of reverse inference.
One of the most obvious mistakes in Fallon's reasoning is called the fallacy of reverse inference.
There is reluctance to use aggregated data in many disciplines, which at least partly is due to the fear of committing the 'ecological fallacy,' or the fallacy of making inferences about relations between variables at the individual level from observed relations at an aggregated level.
As emphasized in a joke attributed to American philosopher Morris Raphael Cohen (1880 1947), logic texts had to be divided in two parts: in the first part, on deductive logic, unwarranted forms of inference (deductive fallacies) are exposed; in the second part, on inductive logic, they are endorsed (see Meehl 1990, 110).
Lots of work from the earliest focuses on fallacies and inference in the context of formal debate.
A theory of deductive fallacies, therefore, is limited to examining common violations of inference rules and the sources of their superficial plausibility.
Formal fallacies are invalid inferences which "bear a superficial resemblance" to valid forms of inference, so these we may think of as deductive fallacies.
Several recent commentators have asked what the medieval theory of modes of common personal supposition was: was it a theory of inference, of quantification, of truth-conditions, of fallacies, or what?
Because the rules of inference of deductive logic are definitory, there cannot exist a theory of deductive fallacies that is independent of the study of these rules.
