Negative conclusion from affirmative premises

A negative conclusion from affirmative premises (also illicit affirmative) occurs when a categorical syllogism has a negative conclusion, but two affirmative premises.

Cogito ergo sum
Logic and rhetoric
Key articles
General logic
Bad logic
v - t - e
Not to be confused with negative proof or affirmative conclusion from a negative premise.

It is a syllogistical fallacy and a formal fallacy.

Forms

You commit this fallacy if you use either of the following false syllogisms:

P1: Some A are B.
P2: Some B are C.
C: Some A are not C
P1: Some A are B.
P2: Some B are C.
C: No A are C.
gollark: Perhaps it's easier if the containment unit magically™ reduces the total mass.
gollark: Time travel seems pretty hard to reason about for our operating-in-linear-time brains.
gollark: I have never heard anyone use slyce or, well, anything but bit, byte and occasionally nybble before.
gollark: Flip-flop things not implemented on top of other gates would be stateful, wouldn't they?
gollark: SRAM cells need power constantly or they lose data.

See also

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