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Categorical Propositions Immediate inferences Blah
Categorical Proposition Types
CodeQuantityQualityExpositionDistribution
AUniversalAffirmativeAll S are P Subject
EUniversalNegativeNo S are PSubject
Predicate
IParticularAffirmativeSome S are P-
OParticularNegativeSome S are not PPredicate
(No P is in the class referred to by "some S")
Immediate Inferences: Eduction
InferenceProcessValidity
AEIO
All S is PNo S is PSome S is PSome S is not P
Simple ConvErsIonInterchange subject and predicate No
All P is S
Yes
No P is S
Yes
Some P is S
No
(Some P is not S)
per AccidEns ConversionInterchange subject and predicate
Invert quantity
Yes
Some P is S
Yes
Some P is not S
NoNo
ObversionChange quality, invert predicate Yes
No S is non-P
Yes
All S is non-P
Yes
Some S is not non-P
Yes
Some S is non-P
ContrApOsitionInvert subject and predicate,
Exchange subject and predicate
Yes
All non-P is non-S
By limitation
Some non-P is non-S
No
(Some non-P is non-S)
Yes
Some non-P is not non-S
Syllogism Validity Rules
  1. Relating to structure
    1. There are only three terms in a syllogism (by definition).
    2. The middle term is not in the conclusion (by definition).
    3. The major premise contains the predicate (major term) of the conclusion (by definition).
    4. The minor premise containes the subject (minor term) of the conclusion (by definition).
  2. Relating to premises irrespective of conclusion or figure
    1. No inference can be made from two negative premises, i.e., at least one premise must be affirmative. (Fallacy of Exclusive Premises)
    2. No inference can be made from two particular premises, i.e., at least one premise must be universal.
  3. Relating to propositions irrespective of figure
    1. If one premise is negative, the conclusion must be negative. (Fallacy of Drawing an Affirmative Conclusion from a Negative Premise)
    2. In extensional logic, if both premises are universal, the conclusion must be universal. (Existential Fallacy)
      This is not a necessary condition for validity if empty classes are disallowed
    3. If both premises are affirmative, the conclusion must be affirmative -
      A negative conclusion requires a negative premise (Fallacy of Drawing a Negative Conclusion from Affirmative Premises)
    4. If one premise is particular, the conclusion must be particular.
  4. Relating to the distribution of terms
    1. The middle term must be distributed in at least one premise (Fallacy of the Undistributed Middle)
    2. A predicate distributed in the conclusion must be distributed in the major premise. (Fallacy of the Illicit Major)
    3. A subject distributed in the conclusion must be distributed in the minor premise. (Fallacy of the Illicit Minor)
    4. The quantity of a term cannot become greater in the conclusion.
Figure1234
Major PremiseM - PP - MM - PP - M
Minor PremiseS - MS - MM - SM - S
ConclusionS - PS - PS - PS - P
Mood
Figure
ExplicationDistributed terms
Premises : Conclusion
Rules violatedValidity
AAA1All M are P
All S are M
All S are P
2 : 1-Valid 1
AAE1All M are P
All S are M
No S are P
2 : 2Affirmative premises, Negative conclusion
Illicit Major
Invalid
AAI1All M are P
All S are M
Some S are P
2 : 0Existential FallacyConditionally Valid 2
AAO1All M are P
All S are M
Some S are not P
2 : 1Affirmative premises, Negative conclusion
Illicit Major
Existential Fallacy
Invalid
AEA1All M are P
No S are M
All S are P
3 : 1Negative premise, affirmative conclusionInvalid
AEE1All M are P
No S are M
No S are P
3 : 2Illicit MajorInvalid
AEI1All M are P
No S are M
Some S are P
3 : 0Negative premise, affirmative conclusion
Existential Fallacy
Invalid
AEO1All M are P
No S are M
Some S are not P
3 : 1Illicit Major
Existential Fallacy
Invalid
AIA1All M are P
Some S are M
All S are P
1 : 1Illicit MinorInvalid
AIE1All M are P
Some S are M
No S are P
1 : 2Affirmative premises, Negative conclusion
Illicit Major
Illicit Minor
Invalid
AII1All M are P
Some S are M
Some S are P
1 : 0-Valid 3
AIO1All M are P
Some S are M
Some S are not P
1 : 1Affirmative premises, Negative conclusion
Illicit Major
Invalid
AOA1All M are P
Some S are not M
All S are P
2 : 1Negative premise, affirmative conclusion
Illicit Minor
Invalid
AOE1All M are P
Some S are not M
No S are P
2 : 2Illicit Major
Illicit Minor
Invalid
AOI1All M are P
Some S are not M
Some S are P
2 : 0Negative premise, affirmative conclusionInvalid
AOO1All M are P
Some S are not M
Some S are not P
2 : 1Illicit MajorInvalid
EAA1No M are P
All S are M
All S are P
3 : 1Negative premise, affirmative conclusionInvalid
EAE1No M are P
All S are M
No S are P
3 : 2-Valid 4
EAI1No M are P
All S are M
Some S are P
3 : 0Negative premise, affirmative conclusion
Existential Fallacy
Invalid
EAO1No M are P
All S are M
Some S are not P
3 : 1Existential FallacyConditionally Valid 5
EEA1No M are P
No S are M
All S are P
4 : 12 negative premises
Negative premise, affirmative conclusion
Invalid
EEE1No M are P
No S are M
No S are P
4 : 22 negative premisesInvalid
EEI1No M are P
No S are M
Some S are P
4 : 02 negative premises
Negative premise, affirmative conclusion
Existential Fallacy
Invalid
EEO1No M are P
No S are M
Some S are not P
4 : 12 negative premises
Existential Fallacy
Invalid
EIA1No M are P
Some S are M
All S are P
2 : 1Negative premise, affirmative conclusion
Illicit Minor
Invalid
EIE1No M are P
Some S are M
No S are P
2 : 2Illicit MinorInvalid
EII1No M are P
Some S are M
Some S are P
2 : 0Negative premise, affirmative conclusionInvalid
EIO1No M are P
Some S are M
Some S are not P
2 : 1-Valid 6
EOA1No M are P
Some S are not M
All S are P
3 : 12 negative premises
Negative premise, affirmative conclusion
Illicit Minor
Invalid
EOE1No M are P
Some S are not M
No S are P
3 : 22 negative premises
Illicit Minor
Invalid
EOI1No M are P
Some S are not M
Some S are P
3 : 02 negative premises
Negative premise, affirmative conclusion
Invalid
EOO1No M are P
Some S are not M
Some S are not P
3 : 12 negative premisesInvalid
IAA1Some M are P
All S are M
All S are P
1 : 1Undistributed MiddleInvalid
IAE1Some M are P
All S are M
No S are P
1 : 2Affirmative premises, Negative conclusion
Undistributed Middle
Illicit Major
Invalid
IAI1Some M are P
All S are M
Some S are P
1 : 0Undistributed MiddleInvalid
IAO1Some M are P
All S are M
Some S are not P
1 : 1Affirmative premises, Negative conclusion
Undistributed Middle
Illicit Major
Invalid
IEA1Some M are P
No S are M
All S are P
2 : 1Negative premise, affirmative conclusionInvalid
IEE1Some M are P
No S are M
No S are P
2 : 2Illicit MajorInvalid
IEI1Some M are P
No S are M
Some S are P
2 : 0Negative premise, affirmative conclusionInvalid
IEO1Some M are P
No S are M
Some S are not P
2 : 1Illicit MajorInvalid
IIA1Some M are P
Some S are M
All S are P
0 : 1Undistributed Middle
Illicit Minor
Invalid
IIE1Some M are P
Some S are M
No S are P
0 : 2Affirmative premises, Negative conclusion
Undistributed Middle
Illicit Major
Illicit Minor
Invalid
III1Some M are P
Some S are M
Some S are P
0 : 0Undistributed MiddleInvalid
IIO1Some M are P
Some S are M
Some S are not P
0 : 1Affirmative premises, Negative conclusion
Undistributed Middle
Illicit Major
Invalid
IOA1Some M are P
Some S are not M
All S are P
1 : 1Negative premise, affirmative conclusion
Illicit Minor
Invalid
IOE1Some M are P
Some S are not M
No S are P
1 : 2Illicit Major
Illicit Minor
Invalid
IOI1Some M are P
Some S are not M
Some S are P
1 : 0Negative premise, affirmative conclusionInvalid
IOO1Some M are P
Some S are not M
Some S are not P
1 : 1Illicit MajorInvalid
OAA1Some M are not P
All S are M
All S are P
2 : 1Negative premise, affirmative conclusion
Undistributed Middle
Invalid
OAE1Some M are not P
All S are M
No S are P
2 : 2Undistributed MiddleInvalid
OAI1Some M are not P
All S are M
Some S are P
2 : 0Negative premise, affirmative conclusion
Undistributed Middle
Invalid
OAO1Some M are not P
All S are M
Some S are not P
2 : 1Undistributed MiddleInvalid
OEA1Some M are not P
No S are M
All S are P
3 : 12 negative premises
Negative premise, affirmative conclusion
Invalid
OEE1Some M are not P
No S are M
No S are P
3 : 22 negative premisesInvalid
OEI1Some M are not P
No S are M
Some S are P
3 : 02 negative premises
Negative premise, affirmative conclusion
Invalid
OEO1Some M are not P
No S are M
Some S are not P
3 : 12 negative premisesInvalid
OIA1Some M are not P
Some S are M
All S are P
1 : 1Negative premise, affirmative conclusion
Undistributed Middle
Illicit Minor
Invalid
OIE1Some M are not P
Some S are M
No S are P
1 : 2Undistributed Middle
Illicit Minor
Invalid
OII1Some M are not P
Some S are M
Some S are P
1 : 0Negative premise, affirmative conclusion
Undistributed Middle
Invalid
OIO1Some M are not P
Some S are M
Some S are not P
1 : 1Undistributed MiddleInvalid
OOA1Some M are not P
Some S are not M
All S are P
2 : 12 negative premises
Negative premise, affirmative conclusion
Illicit Minor
Invalid
OOE1Some M are not P
Some S are not M
No S are P
2 : 22 negative premises
Illicit Minor
Invalid
OOI1Some M are not P
Some S are not M
Some S are P
2 : 02 negative premises
Negative premise, affirmative conclusion
Invalid
OOO1Some M are not P
Some S are not M
Some S are not P
2 : 12 negative premisesInvalid
AAA2All P are M
All S are M
All S are P
2 : 1Undistributed MiddleInvalid
AAE2All P are M
All S are M
No S are P
2 : 2Affirmative premises, Negative conclusion
Undistributed Middle
Invalid
AAI2All P are M
All S are M
Some S are P
2 : 0Undistributed Middle
Existential Fallacy
Invalid
AAO2All P are M
All S are M
Some S are not P
2 : 1Affirmative premises, Negative conclusion
Undistributed Middle
Existential Fallacy
Invalid
AEA2All P are M
No S are M
All S are P
3 : 1Negative premise, affirmative conclusionInvalid
AEE2All P are M
No S are M
No S are P
3 : 2-Valid 7
AEI2All P are M
No S are M
Some S are P
3 : 0Negative premise, affirmative conclusion
Existential Fallacy
Invalid
AEO2All P are M
No S are M
Some S are not P
3 : 1Existential FallacyConditionally Valid 8
AIA2All P are M
Some S are M
All S are P
1 : 1Undistributed Middle
Illicit Minor
Invalid
AIE2All P are M
Some S are M
No S are P
1 : 2Affirmative premises, Negative conclusion
Undistributed Middle
Illicit Minor
Invalid
AII2All P are M
Some S are M
Some S are P
1 : 0Undistributed MiddleInvalid
AIO2All P are M
Some S are M
Some S are not P
1 : 1Affirmative premises, Negative conclusion
Undistributed Middle
Invalid
AOA2All P are M
Some S are not M
All S are P
2 : 1Negative premise, affirmative conclusion
Illicit Minor
Invalid
AOE2All P are M
Some S are not M
No S are P
2 : 2Illicit MinorInvalid
AOI2All P are M
Some S are not M
Some S are P
2 : 0Negative premise, affirmative conclusionInvalid
AOO2All P are M
Some S are not M
Some S are not P
2 : 1-Valid 9
EAA2No P are M
All S are M
All S are P
3 : 1Negative premise, affirmative conclusionInvalid
EAE2No P are M
All S are M
No S are P
3 : 2-Valid 10
EAI2No P are M
All S are M
Some S are P
3 : 0Negative premise, affirmative conclusion
Existential Fallacy
Invalid
EAO2No P are M
All S are M
Some S are not P
3 : 1Existential FallacyConditionally Valid 11
EEA2No P are M
No S are M
All S are P
4 : 12 negative premises
Negative premise, affirmative conclusion
Invalid
EEE2No P are M
No S are M
No S are P
4 : 22 negative premisesInvalid
EEI2No P are M
No S are M
Some S are P
4 : 02 negative premises
Negative premise, affirmative conclusion
Existential Fallacy
Invalid
EEO2No P are M
No S are M
Some S are not P
4 : 12 negative premises
Existential Fallacy
Invalid
EIA2No P are M
Some S are M
All S are P
2 : 1Negative premise, affirmative conclusion
Illicit Minor
Invalid
EIE2No P are M
Some S are M
No S are P
2 : 2Illicit MinorInvalid
EII2No P are M
Some S are M
Some S are P
2 : 0Negative premise, affirmative conclusionInvalid
EIO2No P are M
Some S are M
Some S are not P
2 : 1-Valid 12
EOA2No P are M
Some S are not M
All S are P
3 : 12 negative premises
Negative premise, affirmative conclusion
Illicit Minor
Invalid
EOE2No P are M
Some S are not M
No S are P
3 : 22 negative premises
Illicit Minor
Invalid
EOI2No P are M
Some S are not M
Some S are P
3 : 02 negative premises
Negative premise, affirmative conclusion
Invalid
EOO2No P are M
Some S are not M
Some S are not P
3 : 12 negative premisesInvalid
IAA2Some P are M
All S are M
All S are P
1 : 1Undistributed MiddleInvalid
IAE2Some P are M
All S are M
No S are P
1 : 2Affirmative premises, Negative conclusion
Undistributed Middle
Illicit Major
Invalid
IAI2Some P are M
All S are M
Some S are P
1 : 0Undistributed MiddleInvalid
IAO2Some P are M
All S are M
Some S are not P
1 : 1Affirmative premises, Negative conclusion
Undistributed Middle
Illicit Major
Invalid
IEA2Some P are M
No S are M
All S are P
2 : 1Negative premise, affirmative conclusionInvalid
IEE2Some P are M
No S are M
No S are P
2 : 2Illicit MajorInvalid
IEI2Some P are M
No S are M
Some S are P
2 : 0Negative premise, affirmative conclusionInvalid
IEO2Some P are M
No S are M
Some S are not P
2 : 1Illicit MajorInvalid
IIA2Some P are M
Some S are M
All S are P
0 : 1Undistributed Middle
Illicit Minor
Invalid
IIE2Some P are M
Some S are M
No S are P
0 : 2Affirmative premises, Negative conclusion
Undistributed Middle
Illicit Major
Illicit Minor
Invalid
III2Some P are M
Some S are M
Some S are P
0 : 0Undistributed MiddleInvalid
IIO2Some P are M
Some S are M
Some S are not P
0 : 1Affirmative premises, Negative conclusion
Undistributed Middle
Illicit Major
Invalid
IOA2Some P are M
Some S are not M
All S are P
1 : 1Negative premise, affirmative conclusion
Illicit Minor
Invalid
IOE2Some P are M
Some S are not M
No S are P
1 : 2Illicit Major
Illicit Minor
Invalid
IOI2Some P are M
Some S are not M
Some S are P
1 : 0Negative premise, affirmative conclusionInvalid
IOO2Some P are M
Some S are not M
Some S are not P
1 : 1Illicit MajorInvalid
OAA2Some P are not M
All S are M
All S are P
2 : 1Negative premise, affirmative conclusionInvalid
OAE2Some P are not M
All S are M
No S are P
2 : 2Illicit MajorInvalid
OAI2Some P are not M
All S are M
Some S are P
2 : 0Negative premise, affirmative conclusionInvalid
OAO2Some P are not M
All S are M
Some S are not P
2 : 1Illicit MajorInvalid
OEA2Some P are not M
No S are M
All S are P
3 : 12 negative premises
Negative premise, affirmative conclusion
Invalid
OEE2Some P are not M
No S are M
No S are P
3 : 22 negative premises
Illicit Major
Invalid
OEI2Some P are not M
No S are M
Some S are P
3 : 02 negative premises
Negative premise, affirmative conclusion
Invalid
OEO2Some P are not M
No S are M
Some S are not P
3 : 12 negative premises
Illicit Major
Invalid
OIA2Some P are not M
Some S are M
All S are P
1 : 1Negative premise, affirmative conclusion
Illicit Minor
Invalid
OIE2Some P are not M
Some S are M
No S are P
1 : 2Illicit Major
Illicit Minor
Invalid
OII2Some P are not M
Some S are M
Some S are P
1 : 0Negative premise, affirmative conclusionInvalid
OIO2Some P are not M
Some S are M
Some S are not P
1 : 1Illicit MajorInvalid
OOA2Some P are not M
Some S are not M
All S are P
2 : 12 negative premises
Negative premise, affirmative conclusion
Illicit Minor
Invalid
OOE2Some P are not M
Some S are not M
No S are P
2 : 22 negative premises
Illicit Major
Illicit Minor
Invalid
OOI2Some P are not M
Some S are not M
Some S are P
2 : 02 negative premises
Negative premise, affirmative conclusion
Invalid
OOO2Some P are not M
Some S are not M
Some S are not P
2 : 12 negative premises
Illicit Major
Invalid
AAA3All M are P
All M are S
All S are P
2 : 1Illicit MinorInvalid
AAE3All M are P
All M are S
No S are P
2 : 2Affirmative premises, Negative conclusion
Illicit Major
Illicit Minor
Invalid
AAI3All M are P
All M are S
Some S are P
2 : 0Existential FallacyConditionally Valid 13
AAO3All M are P
All M are S
Some S are not P
2 : 1Affirmative premises, Negative conclusion
Illicit Major
Existential Fallacy
Invalid
AEA3All M are P
No M are S
All S are P
3 : 1Negative premise, affirmative conclusionInvalid
AEE3All M are P
No M are S
No S are P
3 : 2Illicit MajorInvalid
AEI3All M are P
No M are S
Some S are P
3 : 0Negative premise, affirmative conclusion
Existential Fallacy
Invalid
AEO3All M are P
No M are S
Some S are not P
3 : 1Illicit Major
Existential Fallacy
Invalid
AIA3All M are P
Some M are S
All S are P
1 : 1Illicit MinorInvalid
AIE3All M are P
Some M are S
No S are P
1 : 2Affirmative premises, Negative conclusion
Illicit Major
Illicit Minor
Invalid
AII3All M are P
Some M are S
Some S are P
1 : 0-Valid 14
AIO3All M are P
Some M are S
Some S are not P
1 : 1Affirmative premises, Negative conclusion
Illicit Major
Invalid
AOA3All M are P
Some M are not S
All S are P
2 : 1Negative premise, affirmative conclusionInvalid
AOE3All M are P
Some M are not S
No S are P
2 : 2Illicit MajorInvalid
AOI3All M are P
Some M are not S
Some S are P
2 : 0Negative premise, affirmative conclusionInvalid
AOO3All M are P
Some M are not S
Some S are not P
2 : 1Illicit MajorInvalid
EAA3No M are P
All M are S
All S are P
3 : 1Negative premise, affirmative conclusion
Illicit Minor
Invalid
EAE3No M are P
All M are S
No S are P
3 : 2Illicit MinorInvalid
EAI3No M are P
All M are S
Some S are P
3 : 0Negative premise, affirmative conclusion
Existential Fallacy
Invalid
EAO3No M are P
All M are S
Some S are not P
3 : 1Existential FallacyConditionally Valid 15
EEA3No M are P
No M are S
All S are P
4 : 12 negative premises
Negative premise, affirmative conclusion
Invalid
EEE3No M are P
No M are S
No S are P
4 : 22 negative premisesInvalid
EEI3No M are P
No M are S
Some S are P
4 : 02 negative premises
Negative premise, affirmative conclusion
Existential Fallacy
Invalid
EEO3No M are P
No M are S
Some S are not P
4 : 12 negative premises
Existential Fallacy
Invalid
EIA3No M are P
Some M are S
All S are P
2 : 1Negative premise, affirmative conclusion
Illicit Minor
Invalid
EIE3No M are P
Some M are S
No S are P
2 : 2Illicit MinorInvalid
EII3No M are P
Some M are S
Some S are P
2 : 0Negative premise, affirmative conclusionInvalid
EIO3No M are P
Some M are S
Some S are not P
2 : 1-Valid 16
EOA3No M are P
Some M are not S
All S are P
3 : 12 negative premises
Negative premise, affirmative conclusion
Invalid
EOE3No M are P
Some M are not S
No S are P
3 : 22 negative premisesInvalid
EOI3No M are P
Some M are not S
Some S are P
3 : 02 negative premises
Negative premise, affirmative conclusion
Invalid
EOO3No M are P
Some M are not S
Some S are not P
3 : 12 negative premisesInvalid
IAA3Some M are P
All M are S
All S are P
1 : 1Illicit MinorInvalid
IAE3Some M are P
All M are S
No S are P
1 : 2Affirmative premises, Negative conclusion
Illicit Major
Illicit Minor
Invalid
IAI3Some M are P
All M are S
Some S are P
1 : 0-Valid 17
IAO3Some M are P
All M are S
Some S are not P
1 : 1Affirmative premises, Negative conclusion
Illicit Major
Invalid
IEA3Some M are P
No M are S
All S are P
2 : 1Negative premise, affirmative conclusionInvalid
IEE3Some M are P
No M are S
No S are P
2 : 2Illicit MajorInvalid
IEI3Some M are P
No M are S
Some S are P
2 : 0Negative premise, affirmative conclusionInvalid
IEO3Some M are P
No M are S
Some S are not P
2 : 1Illicit MajorInvalid
IIA3Some M are P
Some M are S
All S are P
0 : 1Undistributed Middle
Illicit Minor
Invalid
IIE3Some M are P
Some M are S
No S are P
0 : 2Affirmative premises, Negative conclusion
Undistributed Middle
Illicit Major
Illicit Minor
Invalid
III3Some M are P
Some M are S
Some S are P
0 : 0Undistributed MiddleInvalid
IIO3Some M are P
Some M are S
Some S are not P
0 : 1Affirmative premises, Negative conclusion
Undistributed Middle
Illicit Major
Invalid
IOA3Some M are P
Some M are not S
All S are P
1 : 1Negative premise, affirmative conclusion
Undistributed Middle
Invalid
IOE3Some M are P
Some M are not S
No S are P
1 : 2Undistributed Middle
Illicit Major
Invalid
IOI3Some M are P
Some M are not S
Some S are P
1 : 0Negative premise, affirmative conclusion
Undistributed Middle
Invalid
IOO3Some M are P
Some M are not S
Some S are not P
1 : 1Undistributed Middle
Illicit Major
Invalid
OAA3Some M are not P
All M are S
All S are P
2 : 1Negative premise, affirmative conclusion
Illicit Minor
Invalid
OAE3Some M are not P
All M are S
No S are P
2 : 2Illicit MinorInvalid
OAI3Some M are not P
All M are S
Some S are P
2 : 0Negative premise, affirmative conclusionInvalid
OAO3Some M are not P
All M are S
Some S are not P
2 : 1-Valid 18
OEA3Some M are not P
No M are S
All S are P
3 : 12 negative premises
Negative premise, affirmative conclusion
Invalid
OEE3Some M are not P
No M are S
No S are P
3 : 22 negative premisesInvalid
OEI3Some M are not P
No M are S
Some S are P
3 : 02 negative premises
Negative premise, affirmative conclusion
Invalid
OEO3Some M are not P
No M are S
Some S are not P
3 : 12 negative premisesInvalid
OIA3Some M are not P
Some M are S
All S are P
1 : 1Negative premise, affirmative conclusion
Undistributed Middle
Illicit Minor
Invalid
OIE3Some M are not P
Some M are S
No S are P
1 : 2Undistributed Middle
Illicit Minor
Invalid
OII3Some M are not P
Some M are S
Some S are P
1 : 0Negative premise, affirmative conclusion
Undistributed Middle
Invalid
OIO3Some M are not P
Some M are S
Some S are not P
1 : 1Undistributed MiddleInvalid
OOA3Some M are not P
Some M are not S
All S are P
2 : 12 negative premises
Negative premise, affirmative conclusion
Undistributed Middle
Invalid
OOE3Some M are not P
Some M are not S
No S are P
2 : 22 negative premises
Undistributed Middle
Invalid
OOI3Some M are not P
Some M are not S
Some S are P
2 : 02 negative premises
Negative premise, affirmative conclusion
Undistributed Middle
Invalid
OOO3Some M are not P
Some M are not S
Some S are not P
2 : 12 negative premises
Undistributed Middle
Invalid
AAA4All P are M
All M are S
All S are P
2 : 1Illicit MinorInvalid
AAE4All P are M
All M are S
No S are P
2 : 2Affirmative premises, Negative conclusion
Illicit Minor
Invalid
AAI4All P are M
All M are S
Some S are P
2 : 0Existential FallacyConditionally Valid 19
AAO4All P are M
All M are S
Some S are not P
2 : 1Affirmative premises, Negative conclusion
Existential Fallacy
Invalid
AEA4All P are M
No M are S
All S are P
3 : 1Negative premise, affirmative conclusionInvalid
AEE4All P are M
No M are S
No S are P
3 : 2-Valid 20
AEI4All P are M
No M are S
Some S are P
3 : 0Negative premise, affirmative conclusion
Existential Fallacy
Invalid
AEO4All P are M
No M are S
Some S are not P
3 : 1Existential FallacyConditionally Valid 21
AIA4All P are M
Some M are S
All S are P
1 : 1Undistributed Middle
Illicit Minor
Invalid
AIE4All P are M
Some M are S
No S are P
1 : 2Affirmative premises, Negative conclusion
Undistributed Middle
Illicit Minor
Invalid
AII4All P are M
Some M are S
Some S are P
1 : 0Undistributed MiddleInvalid
AIO4All P are M
Some M are S
Some S are not P
1 : 1Affirmative premises, Negative conclusion
Undistributed Middle
Invalid
AOA4All P are M
Some M are not S
All S are P
2 : 1Negative premise, affirmative conclusion
Undistributed Middle
Invalid
AOE4All P are M
Some M are not S
No S are P
2 : 2Undistributed MiddleInvalid
AOI4All P are M
Some M are not S
Some S are P
2 : 0Negative premise, affirmative conclusion
Undistributed Middle
Invalid
AOO4All P are M
Some M are not S
Some S are not P
2 : 1Undistributed MiddleInvalid
EAA4No P are M
All M are S
All S are P
3 : 1Negative premise, affirmative conclusion
Illicit Minor
Invalid
EAE4No P are M
All M are S
No S are P
3 : 2Illicit MinorInvalid
EAI4No P are M
All M are S
Some S are P
3 : 0Negative premise, affirmative conclusion
Existential Fallacy
Invalid
EAO4No P are M
All M are S
Some S are not P
3 : 1Existential FallacyConditionally Valid 22
EEA4No P are M
No M are S
All S are P
4 : 12 negative premises
Negative premise, affirmative conclusion
Invalid
EEE4No P are M
No M are S
No S are P
4 : 22 negative premisesInvalid
EEI4No P are M
No M are S
Some S are P
4 : 02 negative premises
Negative premise, affirmative conclusion
Existential Fallacy
Invalid
EEO4No P are M
No M are S
Some S are not P
4 : 12 negative premises
Existential Fallacy
Invalid
EIA4No P are M
Some M are S
All S are P
2 : 1Negative premise, affirmative conclusion
Illicit Minor
Invalid
EIE4No P are M
Some M are S
No S are P
2 : 2Illicit MinorInvalid
EII4No P are M
Some M are S
Some S are P
2 : 0Negative premise, affirmative conclusionInvalid
EIO4No P are M
Some M are S
Some S are not P
2 : 1-Valid 23
EOA4No P are M
Some M are not S
All S are P
3 : 12 negative premises
Negative premise, affirmative conclusion
Invalid
EOE4No P are M
Some M are not S
No S are P
3 : 22 negative premisesInvalid
EOI4No P are M
Some M are not S
Some S are P
3 : 02 negative premises
Negative premise, affirmative conclusion
Invalid
EOO4No P are M
Some M are not S
Some S are not P
3 : 12 negative premisesInvalid
IAA4Some P are M
All M are S
All S are P
1 : 1Illicit MinorInvalid
IAE4Some P are M
All M are S
No S are P
1 : 2Affirmative premises, Negative conclusion
Illicit Major
Illicit Minor
Invalid
IAI4Some P are M
All M are S
Some S are P
1 : 0-Valid 24
IAO4Some P are M
All M are S
Some S are not P
1 : 1Affirmative premises, Negative conclusion
Illicit Major
Invalid
IEA4Some P are M
No M are S
All S are P
2 : 1Negative premise, affirmative conclusionInvalid
IEE4Some P are M
No M are S
No S are P
2 : 2Illicit MajorInvalid
IEI4Some P are M
No M are S
Some S are P
2 : 0Negative premise, affirmative conclusionInvalid
IEO4Some P are M
No M are S
Some S are not P
2 : 1Illicit MajorInvalid
IIA4Some P are M
Some M are S
All S are P
0 : 1Undistributed Middle
Illicit Minor
Invalid
IIE4Some P are M
Some M are S
No S are P
0 : 2Affirmative premises, Negative conclusion
Undistributed Middle
Illicit Major
Illicit Minor
Invalid
III4Some P are M
Some M are S
Some S are P
0 : 0Undistributed MiddleInvalid
IIO4Some P are M
Some M are S
Some S are not P
0 : 1Affirmative premises, Negative conclusion
Undistributed Middle
Illicit Major
Invalid
IOA4Some P are M
Some M are not S
All S are P
1 : 1Negative premise, affirmative conclusion
Undistributed Middle
Invalid
IOE4Some P are M
Some M are not S
No S are P
1 : 2Undistributed Middle
Illicit Major
Invalid
IOI4Some P are M
Some M are not S
Some S are P
1 : 0Negative premise, affirmative conclusion
Undistributed Middle
Invalid
IOO4Some P are M
Some M are not S
Some S are not P
1 : 1Undistributed Middle
Illicit Major
Invalid
OAA4Some P are not M
All M are S
All S are P
2 : 1Negative premise, affirmative conclusion
Illicit Minor
Invalid
OAE4Some P are not M
All M are S
No S are P
2 : 2Illicit Major
Illicit Minor
Invalid
OAI4Some P are not M
All M are S
Some S are P
2 : 0Negative premise, affirmative conclusionInvalid
OAO4Some P are not M
All M are S
Some S are not P
2 : 1Illicit MajorInvalid
OEA4Some P are not M
No M are S
All S are P
3 : 12 negative premises
Negative premise, affirmative conclusion
Invalid
OEE4Some P are not M
No M are S
No S are P
3 : 22 negative premises
Illicit Major
Invalid
OEI4Some P are not M
No M are S
Some S are P
3 : 02 negative premises
Negative premise, affirmative conclusion
Invalid
OEO4Some P are not M
No M are S
Some S are not P
3 : 12 negative premises
Illicit Major
Invalid
OIA4Some P are not M
Some M are S
All S are P
1 : 1Negative premise, affirmative conclusion
Illicit Minor
Invalid
OIE4Some P are not M
Some M are S
No S are P
1 : 2Illicit Major
Illicit Minor
Invalid
OII4Some P are not M
Some M are S
Some S are P
1 : 0Negative premise, affirmative conclusionInvalid
OIO4Some P are not M
Some M are S
Some S are not P
1 : 1Illicit MajorInvalid
OOA4Some P are not M
Some M are not S
All S are P
2 : 12 negative premises
Negative premise, affirmative conclusion
Invalid
OOE4Some P are not M
Some M are not S
No S are P
2 : 22 negative premises
Illicit Major
Invalid
OOI4Some P are not M
Some M are not S
Some S are P
2 : 02 negative premises
Negative premise, affirmative conclusion
Invalid
OOO4Some P are not M
Some M are not S
Some S are not P
2 : 12 negative premises
Illicit Major
Invalid