Secundum Quid

See Accident and Converse Accident, two versions of the fallacy.

Converse Accident

If we reason by paying too much attention to exceptions to the rule, and generalize on the exceptions, we commit this fallacy. This fallacy is the converse of the accident fallacy. It is a kind of Hasty Generalization.

Example:

I've heard that turtles live longer than tarantulas, but the one turtle I bought lived only two days. I bought it at Dowden's Pet Store. So, I think that turtles bought from pet stores do not live longer than tarantulas.

The original generalization is "Turtles live longer than tarantulas." There are exceptions, such as the turtle bought from the pet store. Rather than seeing this for what it is, namely an exception, the reasoner places too much trust in this exception and generalizes on it to produce the faulty generalization that turtles bought from pet stores do not live longer than tarantulas.