Fallacies of Context:
False Alternative

When we reason about the truth or falsity of a conclusion, we rarely consider the conclusion in a vacuum. Instead, we have in mind a range of other possible conclusions. When we think about whether to take a certain action, we weigh it against other actions. When we consider a hypothesis to explain why something happened, we test it against other hypotheses. In short, thinking often involves a choice among alternatives.

The fallacy of false alternative occurs when we fail to consider all the relevant possibilities.

One form occurs when we consider only the extreme points of a scale. If you told me that Diane is not rich, I would commit the fallacy if I inferred that she is poor. Rich and poor are the extremes on a scale that contains many intermediate degrees of wealth.

The most subtle examples of the fallacy are those in which relevant alternatives are excluded by some implicit, unspoken, and thus invisible assumption.

False alternative | Post hoc |
Hasty generalization | Composition | Division

Fallacies of Context

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