Welcome to HSLC GURU. This page provides the complete Class 11 Logic and Philosophy Chapter 5 Question Answer | Distribution of Terms | English Medium | ASSEB solutions. The chapter Distribution of Terms is a foundational topic of traditional Aristotelian logic. It explains when a term in a proposition refers to the whole class denoted by it (distributed) and when it refers only to a part (undistributed). A clear understanding of distribution is necessary for solving categorical syllogisms, applying rules of immediate inference, and testing the validity of arguments. The notes below cover definitions, the distribution table for the four categorical propositions A, E, I, O, the quick rule, Euler diagrams, worked examples, and a complete set of textbook and additional questions prescribed under the Assam State School Education Board (ASSEB / AHSEC) syllabus.
Chapter Summary
A categorical proposition contains two terms, the subject and the predicate. Distribution is a property of these terms inside a proposition. A term is said to be distributed when the proposition refers to the whole or entire denotation (extension) of that term, that is, to all members of the class. A term is undistributed when the proposition refers only to a part of its denotation. Distribution does not depend on what a term means in isolation; it depends on how the term is used in the proposition.
The four standard forms of categorical propositions are A (universal affirmative), E (universal negative), I (particular affirmative) and O (particular negative). The pattern of distribution for these four types can be summarised by a single quick rule: universal propositions distribute the subject; negative propositions distribute the predicate. From this it follows that A distributes only the subject, E distributes both subject and predicate, I distributes neither, and O distributes only the predicate.
The doctrine of distribution is important because most of the rules of categorical syllogism, conversion, obversion and other immediate inferences are stated in terms of distributed and undistributed terms. For example, in syllogism the middle term must be distributed at least once, and a term distributed in the conclusion must also be distributed in the premise. Without knowing distribution, one cannot test the validity of a syllogism.
Key Definitions
| Term | Definition |
|---|---|
| Distribution of a term | A term is said to be distributed in a proposition when it is taken in its entire denotation, that is, when the proposition makes a statement about all the members of the class denoted by that term. |
| Distributed term | A term referring to all members of its class as used in the proposition. |
| Undistributed term | A term referring only to some members (a part) of the class denoted by it. |
| Denotation / Extension | The class of all individuals or things to which a term applies. |
| Connotation / Intension | The qualities or attributes implied by a term. |
The Quick Rule of Distribution
The whole doctrine can be remembered through one short rule:
| Rule | Meaning |
|---|---|
| Universal propositions distribute their subject. | A and E distribute the subject term, because they speak about the whole subject class. |
| Negative propositions distribute their predicate. | E and O distribute the predicate term, because a negative proposition excludes the subject from the whole of the predicate class. |
| Particular propositions do not distribute the subject. | I and O speak only of “some” of the subject. |
| Affirmative propositions do not distribute the predicate. | A and I do not exclude the subject from any part of the predicate class. |
Distribution Table for A, E, I, O Propositions
| Proposition | Form / Type | Example | Subject (S) | Predicate (P) |
|---|---|---|---|---|
| A | Universal Affirmative (All S is P) |
All men are mortal. | Distributed | Undistributed |
| E | Universal Negative (No S is P) |
No men are perfect. | Distributed | Distributed |
| I | Particular Affirmative (Some S is P) |
Some men are wise. | Undistributed | Undistributed |
| O | Particular Negative (Some S is not P) |
Some men are not honest. | Undistributed | Distributed |
Detailed Explanation with Examples
1. A Proposition (Universal Affirmative)
Example: All men are mortal.
Here the proposition speaks about every member of the class “men”, so the subject term “men” is taken in its entire denotation and is therefore distributed. The predicate “mortal”, however, is not taken in its full extension, because the proposition does not say that “all mortal beings are men”. The class of mortal beings includes other animals as well; only a part of that class is being referred to. Hence the predicate is undistributed.
Euler Diagram: The circle of S (men) lies entirely inside the larger circle of P (mortals).
2. E Proposition (Universal Negative)
Example: No men are perfect.
The proposition denies the predicate of every member of the subject class, so the subject “men” is distributed. It also excludes the whole subject class from the whole predicate class, so the predicate “perfect (beings)” is also distributed. In a universal negative, both classes are completely separated.
Euler Diagram: The two circles S and P stand entirely apart, with no overlap.
3. I Proposition (Particular Affirmative)
Example: Some men are wise.
“Some” indicates only a part of the class men, so the subject is undistributed. The predicate “wise” is also not taken in its full extension because the proposition does not say “all wise persons are men”. Only a part of the class of wise persons is being identified with a part of men. Hence the predicate is also undistributed.
Euler Diagram: The circles S and P partly overlap; the part of overlap shows the “some” who are both.
4. O Proposition (Particular Negative)
Example: Some men are not honest.
The subject “men” is referred to only in part, so it is undistributed. The predicate “honest”, however, is taken in its full denotation, because the proposition excludes a part of men from the entire class of honest beings. To say that some S is not P is to say that those S are excluded from every P. Hence the predicate is distributed.
Euler Diagram: A part of S falls outside the whole circle of P.
Why Predicate is Distributed in Negative Propositions
In any negative proposition, the subject is denied of the predicate. To deny the predicate of the subject means to exclude the subject from every member of the predicate class. If even one member of P were left out of this exclusion, the denial would not be complete. Therefore, in E (“No S is P”) and O (“Some S is not P”), the predicate is always taken in its full denotation, that is, distributed.
Why Predicate is Undistributed in Affirmative Propositions
In an affirmative proposition the subject is identified only with a part of the predicate class, not with the whole of it. For instance, “All men are mortal” identifies men with a portion of mortals, not with the whole class of mortals. Hence the predicate of A and I is undistributed.
Importance of Distribution in Syllogism
| Use | Explanation |
|---|---|
| Rule of the Middle Term | The middle term must be distributed at least once in the premises; otherwise the syllogism commits the fallacy of undistributed middle. |
| Rule of the Major and Minor Terms | If a term is distributed in the conclusion, it must also be distributed in its premise; otherwise the fallacy of illicit major or illicit minor occurs. |
| Conversion | A term that is undistributed in the original proposition (convertend) cannot be distributed in the converse. This is why A converts only to I (per accidens). |
| Obversion and Contraposition | Distribution helps in checking whether the inferred proposition validly follows from the original. |
Worked Examples
Example 1: “All students are intelligent.” State the distribution of subject and predicate.
Answer: This is an A proposition. Subject “students” is distributed; predicate “intelligent” is undistributed.
Example 2: “No politicians are saints.” State the distribution.
Answer: This is an E proposition. Both subject “politicians” and predicate “saints” are distributed.
Example 3: “Some flowers are red.” State the distribution.
Answer: This is an I proposition. Both subject “flowers” and predicate “red things” are undistributed.
Example 4: “Some metals are not magnetic.” State the distribution.
Answer: This is an O proposition. Subject “metals” is undistributed; predicate “magnetic things” is distributed.
Example 5: “Every triangle has three sides.” Identify the proposition and state distribution.
Answer: “Every triangle has three sides” is logically an A proposition: All triangles are three-sided figures. Subject “triangles” is distributed; predicate “three-sided figures” is undistributed.
Textbook Questions and Answers
Very Short / One-Mark Questions
Q1. What is meant by distribution of a term?
Answer: A term is said to be distributed in a proposition when it is taken in its entire denotation, i.e., when it refers to all the members of the class denoted by it.
Q2. When is a term said to be undistributed?
Answer: A term is undistributed when the proposition refers only to a part, not the whole, of the class denoted by it.
Q3. Which proposition distributes both its terms?
Answer: The E proposition (universal negative) distributes both its subject and its predicate.
Q4. Which proposition distributes neither of its terms?
Answer: The I proposition (particular affirmative) distributes neither the subject nor the predicate.
Q5. Which proposition distributes only its predicate?
Answer: The O proposition (particular negative) distributes only its predicate.
Q6. Which proposition distributes only its subject?
Answer: The A proposition (universal affirmative) distributes only its subject.
Q7. State the quick rule of distribution.
Answer: Universal propositions distribute their subject; negative propositions distribute their predicate.
Q8. Is the predicate of “All men are mortal” distributed?
Answer: No. In an A proposition the predicate is undistributed.
Q9. Is the subject of “Some students are not lazy” distributed?
Answer: No. In an O proposition the subject is undistributed.
Q10. In “No man is immortal”, which terms are distributed?
Answer: Both the subject “man” and the predicate “immortal” are distributed.
Q11. Give an example of a proposition where neither term is distributed.
Answer: “Some men are honest.” (I proposition)
Q12. The doctrine of distribution applies to which propositions?
Answer: It applies to the four standard categorical propositions: A, E, I and O.
Short Answer Questions (2-3 Marks)
Q13. Define distributed and undistributed terms with one example each.
Answer: A term is distributed when it is used in a proposition to refer to the whole of the class it denotes. Example: “men” in “All men are mortal” refers to every man, so it is distributed. A term is undistributed when it refers only to a part of its class. Example: “mortal” in “All men are mortal” refers only to some mortal beings (those who are men), so it is undistributed.
Q14. Why is the subject distributed in a universal proposition?
Answer: A universal proposition makes a statement about every member of the subject class. Whether it affirms (A) or denies (E) the predicate, it does so of all the members of the subject. Therefore the subject is taken in its entire denotation and is distributed.
Q15. Why is the predicate distributed in a negative proposition?
Answer: A negative proposition denies the predicate of the subject. To deny means to exclude the subject from every member of the predicate class, not from a few only. Hence the predicate is taken in its full denotation and is distributed.
Q16. Why is the predicate undistributed in an affirmative proposition?
Answer: An affirmative proposition identifies the subject with only a part of the predicate class. For example, “All men are mortal” identifies men with some of the mortals, not with all mortal beings. Therefore the predicate of A and I propositions is undistributed.
Q17. State the distribution of terms in the following propositions: (a) All birds are animals, (b) No fish is a mammal, (c) Some students are clever, (d) Some politicians are not honest.
Answer:
| Proposition | Type | Subject | Predicate |
|---|---|---|---|
| (a) All birds are animals | A | Distributed | Undistributed |
| (b) No fish is a mammal | E | Distributed | Distributed |
| (c) Some students are clever | I | Undistributed | Undistributed |
| (d) Some politicians are not honest | O | Undistributed | Distributed |
Q18. Why is the doctrine of distribution important in logic?
Answer: The doctrine of distribution is important because the rules of categorical syllogism and the rules of immediate inference (conversion, obversion, contraposition) are stated in terms of distributed and undistributed terms. Without knowing the distribution of terms, one cannot test the validity of an argument or detect fallacies such as undistributed middle, illicit major, or illicit minor.
Q19. What is the difference between distribution of a term and denotation of a term?
Answer: Denotation refers to the entire class of objects to which a term may apply, considered apart from any proposition. Distribution refers to the use of a term in a particular proposition: a term is distributed only if that proposition refers to the whole denotation of the term. The same term may be distributed in one proposition and undistributed in another.
Long Answer Questions (4-6 Marks)
Q20. Explain the doctrine of distribution of terms with reference to the four categorical propositions A, E, I and O.
Answer: Distribution of a term is its property of being taken in its entire denotation in a proposition. A term is distributed when the proposition refers to the whole class denoted by the term, and undistributed when it refers only to a part. Categorical propositions are of four kinds:
- A (Universal Affirmative – All S is P): Subject is distributed because it speaks of every S; predicate is undistributed because S is identified only with a part of P. Example: All men are mortal.
- E (Universal Negative – No S is P): Subject is distributed because every S is being referred to; predicate is also distributed because S is excluded from the whole class of P. Example: No men are perfect.
- I (Particular Affirmative – Some S is P): Subject is undistributed because only some S are referred to; predicate is undistributed because only some P are identified with S. Example: Some men are wise.
- O (Particular Negative – Some S is not P): Subject is undistributed because only some S are referred to; predicate is distributed because those S are excluded from the whole class of P. Example: Some men are not honest.
The whole rule may be summarised as: universal propositions distribute the subject and negative propositions distribute the predicate.
Q21. Discuss the importance of distribution of terms in logic.
Answer: Distribution of terms is one of the most useful concepts of formal logic because almost every formal rule of valid reasoning is expressed in terms of distribution.
- In Syllogism: The general rules of categorical syllogism are based on distribution. The middle term must be distributed at least once; otherwise the fallacy of undistributed middle occurs. Any term distributed in the conclusion must be distributed in its premise; otherwise the fallacy of illicit major or illicit minor results.
- In Conversion: A term that is undistributed in the convertend cannot be distributed in the converse. This is why an A proposition can be converted only to an I (conversion per accidens).
- In Obversion and Contraposition: The validity of these immediate inferences is also tested by examining how distribution is preserved.
- In Detecting Fallacies: Many formal fallacies arise from violating distribution rules, so a clear knowledge of distribution helps in identifying them.
Hence, the doctrine of distribution is the very backbone of the formal study of categorical logic.
Q22. Explain with the help of Euler’s diagrams the distribution of terms in A, E, I, and O propositions.
Answer: Euler’s circles represent the classes denoted by the subject (S) and the predicate (P).
- A – All S is P: Circle S lies wholly inside circle P. The whole of S is referred to (distributed), but only a part of P is referred to (undistributed).
- E – No S is P: Circles S and P stand completely apart. The whole of S is excluded from the whole of P, so both terms are distributed.
- I – Some S is P: Circles S and P overlap partially. Only a part of S coincides with a part of P, so neither is distributed.
- O – Some S is not P: Part of circle S lies outside the whole of circle P. Subject is partly referred to (undistributed), but the predicate is wholly excluded (distributed).
Thus the diagrams visually confirm the standard distribution table for A, E, I, O propositions.
Q23. “Distribution depends on the use of a term in a proposition, not on its meaning.” Explain.
Answer: The same term may be distributed in one proposition and undistributed in another, because distribution is not a property of the term in isolation but of the term as it occurs in a particular proposition. For example, the term “men” is distributed in “All men are mortal” (A proposition, subject), but it is undistributed in “Some men are wise” (I proposition, subject). Similarly, “mortal” is undistributed in “All men are mortal” (predicate of A) but distributed in “No animals are mortal” (predicate of E). Hence distribution is determined entirely by the structure and quality of the proposition in which the term occurs.
Additional / Important Questions
Q24. Fill in the blanks: In an A proposition, the subject is ______ and the predicate is ______.
Answer: Distributed; Undistributed.
Q25. Fill in the blanks: In an O proposition, the subject is ______ and the predicate is ______.
Answer: Undistributed; Distributed.
Q26. State whether the following statement is true or false: “In an I proposition, the predicate is distributed.”
Answer: False. In an I proposition, both subject and predicate are undistributed.
Q27. State whether true or false: “In an E proposition, only the subject is distributed.”
Answer: False. In an E proposition both subject and predicate are distributed.
Q28. Identify the proposition in which the predicate is distributed but the subject is not.
Answer: The O proposition (particular negative).
Q29. Convert “All men are mortal” and check whether the predicate becomes distributed.
Answer: “All men are mortal” (A) converts to “Some mortals are men” (I) by conversion per accidens. In the converse, “mortals” is the subject of an I proposition and remains undistributed; this is consistent with the rule that a term undistributed in the original cannot become distributed in the converse.
Q30. Why does an A proposition not convert simply to another A?
Answer: In “All S is P”, the predicate P is undistributed. If we converted it simply to “All P is S”, P would suddenly become distributed (as subject of A), which is logically illegitimate. Therefore A is converted only by limitation into an I proposition.
Q31. State the distribution of terms in: “Every honest man is respected.”
Answer: Logical form: All honest men are respected persons (A). Subject distributed; predicate undistributed.
Q32. State the distribution in: “No virtuous man is unhappy.”
Answer: Form: E proposition. Both subject “virtuous men” and predicate “unhappy persons” are distributed.
Q33. State the distribution in: “A few players are not disciplined.”
Answer: Form: O proposition (Some players are not disciplined). Subject undistributed, predicate distributed.
Q34. Can a term be distributed in the conclusion of a syllogism if it is not distributed in the premise?
Answer: No. If a term is distributed in the conclusion but undistributed in its premise, the syllogism commits the fallacy of illicit process (illicit major or illicit minor).
Q35. Why must the middle term of a syllogism be distributed at least once?
Answer: If the middle term is not distributed in either premise, it is impossible to relate the major and minor terms through a common class. The result is the fallacy of undistributed middle, and the syllogism becomes invalid.
Q36. Multiple Choice: In which proposition is only the subject distributed? (a) A (b) E (c) I (d) O
Answer: (a) A.
Q37. Multiple Choice: In which proposition is only the predicate distributed? (a) A (b) E (c) I (d) O
Answer: (d) O.
Q38. Multiple Choice: In which proposition are both terms distributed? (a) A (b) E (c) I (d) O
Answer: (b) E.
Q39. Multiple Choice: In which proposition is no term distributed? (a) A (b) E (c) I (d) O
Answer: (c) I.
Q40. Match the following:
| Proposition | Distribution |
|---|---|
| A | Subject distributed only |
| E | Both terms distributed |
| I | Neither distributed |
| O | Predicate distributed only |
Q41. Reduce to logical form and state distribution: “Children love sweets.”
Answer: Logical form: All children are lovers of sweets (A). Subject distributed; predicate undistributed.
Q42. Reduce to logical form and state distribution: “Few politicians are sincere.”
Answer: “Few” indicates a particular negative tone in English logic. Form: Some politicians are not sincere (O). Subject undistributed; predicate distributed.
Q43. Reduce to logical form and state distribution: “Saints are never selfish.”
Answer: Form: No saints are selfish (E). Both terms distributed.
Q44. Reduce and state distribution: “Most students passed.”
Answer: Form: Some students are persons who passed (I). Both terms undistributed.
Q45. Distinguish between extension and distribution of a term.
Answer: Extension (denotation) is the totality of objects to which a term applies, considered independently of any proposition. Distribution refers to the way a term is actually used in a proposition: a term is said to be distributed when the proposition refers to the whole of its extension. So extension belongs to the term, while distribution belongs to the term-in-a-proposition.
Q46. State the formula of distribution invented by traditional logicians.
Answer: “All universals distribute their subjects; all negatives distribute their predicates.” This single statement covers the distribution pattern of all four standard propositions A, E, I, O.
Q47. Why does an I proposition not undergo conversion per accidens?
Answer: An I proposition simply converts into another I (Some S is P → Some P is S), because both terms are undistributed in both forms. Conversion per accidens is unnecessary, since neither term gains distribution.
Q48. State the distribution of: “Diamonds are precious stones.”
Answer: Form: All diamonds are precious stones (A). Subject distributed; predicate undistributed.
Q49. State the distribution of: “Some flowers are not fragrant.”
Answer: Form: O. Subject “flowers” undistributed; predicate “fragrant things” distributed.
Q50. Why is the doctrine of distribution called the key to formal logic?
Answer: Because nearly every rule of valid deductive inference – the rules of syllogism, conversion, obversion and contraposition – is framed in terms of distributed and undistributed terms. Without distribution, formal logic could not state its laws of valid reasoning precisely. Hence it is called the key that unlocks the rules of formal logic.
Glossary of Important Terms
| Term | Meaning |
|---|---|
| Distribution | Use of a term in its entire denotation in a proposition. |
| Distributed term | A term referring to all members of its class. |
| Undistributed term | A term referring only to some members of its class. |
| Subject (S) | The term about which something is affirmed or denied. |
| Predicate (P) | The term that is affirmed or denied of the subject. |
| Quality | Affirmative or negative character of a proposition. |
| Quantity | Universal or particular character of a proposition. |
| Denotation / Extension | The class of all objects denoted by a term. |
| Connotation / Intension | Attributes implied by a term. |
| A Proposition | Universal Affirmative: All S is P. |
| E Proposition | Universal Negative: No S is P. |
| I Proposition | Particular Affirmative: Some S is P. |
| O Proposition | Particular Negative: Some S is not P. |
| Conversion | Immediate inference by interchange of subject and predicate. |
| Undistributed Middle | A syllogistic fallacy in which the middle term is not distributed in either premise. |
| Illicit Major | Fallacy where the major term is distributed in the conclusion but not in the major premise. |
| Illicit Minor | Fallacy where the minor term is distributed in the conclusion but not in the minor premise. |
| Euler’s Diagram | Pictorial representation of class relations using circles. |
Summary Table: AEIO Distribution at a Glance
| Proposition | Symbolic Form | Quantity | Quality | Subject | Predicate |
|---|---|---|---|---|---|
| A | All S is P | Universal | Affirmative | Distributed | Undistributed |
| E | No S is P | Universal | Negative | Distributed | Distributed |
| I | Some S is P | Particular | Affirmative | Undistributed | Undistributed |
| O | Some S is not P | Particular | Negative | Undistributed | Distributed |
Mnemonic to Remember: “Asebino” – A: subject; E: both; I: none; O: predicate. Or simply: Universals distribute subject, Negatives distribute predicate.
Further Worked Examples and Practice
Q51. Examine the following propositions and state which terms are distributed:
| Proposition | Type | Subject | Predicate |
|---|---|---|---|
| All squares are rectangles. | A | Distributed | Undistributed |
| No reptiles are warm-blooded animals. | E | Distributed | Distributed |
| Some Indians are scientists. | I | Undistributed | Undistributed |
| Some teachers are not strict. | O | Undistributed | Distributed |
| All planets are heavenly bodies. | A | Distributed | Undistributed |
| No living being is immortal. | E | Distributed | Distributed |
| Some women are doctors. | I | Undistributed | Undistributed |
| Some books are not interesting. | O | Undistributed | Distributed |
Q52. Why is “Some S is P” said to mean “at least one S is P”?
Answer: In logic the word “some” is interpreted as “at least one and possibly all”. An I proposition therefore asserts only the existence of at least one member of S that is also P. It does not say anything about the rest of the class. Because the proposition speaks only of a part of the subject class, the subject is undistributed. Similarly, only a part of the predicate class is referred to, so the predicate is also undistributed.
Q53. How does the quality and quantity of a proposition together determine the distribution of its terms?
Answer: The quantity of a proposition (universal or particular) determines whether the subject is distributed: universal propositions distribute the subject, particular propositions do not. The quality of a proposition (affirmative or negative) determines whether the predicate is distributed: negative propositions distribute the predicate, affirmative propositions do not. Thus quantity controls the subject and quality controls the predicate.
| Proposition | Quantity decides Subject | Quality decides Predicate |
|---|---|---|
| A (Universal Affirmative) | Universal → Subject Distributed | Affirmative → Predicate Undistributed |
| E (Universal Negative) | Universal → Subject Distributed | Negative → Predicate Distributed |
| I (Particular Affirmative) | Particular → Subject Undistributed | Affirmative → Predicate Undistributed |
| O (Particular Negative) | Particular → Subject Undistributed | Negative → Predicate Distributed |
Q54. Test the validity of the following syllogism using distribution:
All men are mortal.
All Greeks are men.
Therefore, all Greeks are mortal.
Answer: Let M = men (middle), P = mortal (major), S = Greeks (minor).
- Major premise (A): All M is P. M distributed, P undistributed.
- Minor premise (A): All S is M. S distributed, M undistributed.
- Conclusion (A): All S is P. S distributed, P undistributed.
The middle term M is distributed at least once (in the major premise), so there is no fallacy of undistributed middle. P is undistributed in the conclusion, and is also undistributed in the major premise — no illicit major. S is distributed in the conclusion, and is also distributed in the minor premise — no illicit minor. Therefore the syllogism is valid.
Q55. Test the following syllogism using distribution:
All cats are animals.
All dogs are animals.
Therefore, all dogs are cats.
Answer: Middle term M = animals; major term P = cats; minor term S = dogs.
- Major premise (A): All M’ (cats) is P? Actually rewriting: All cats are animals — cats distributed, animals undistributed.
- Minor premise (A): All dogs are animals — dogs distributed, animals undistributed.
- The middle term “animals” appears as the predicate of two A propositions and is undistributed in both premises.
This commits the fallacy of undistributed middle, because the middle term is not distributed in either premise. The argument is therefore invalid.
Q56. Why is the property of distribution called a property of the proposition rather than of the term itself?
Answer: A term in isolation has only its meaning (connotation) and its class of objects (denotation). It is neither distributed nor undistributed by itself. It becomes distributed or undistributed only when it is used as a term in a particular proposition, because distribution depends on whether the proposition refers to the whole or only a part of the term’s denotation. Hence distribution is a function of the proposition.
Q57. State the distribution in: “Whales are not fishes.”
Answer: Logical form: No whales are fishes (E). Both subject and predicate are distributed.
Q58. State the distribution in: “Many Indians are farmers.”
Answer: Form: Some Indians are farmers (I). Subject and predicate both undistributed.
Q59. State the distribution in: “Not all students are sincere.”
Answer: Form: Some students are not sincere (O). Subject undistributed; predicate distributed.
Q60. State the distribution in: “Roses are flowers.”
Answer: Form: All roses are flowers (A). Subject distributed; predicate undistributed.
Common Misconceptions
| Misconception | Correct Position |
|---|---|
| The predicate of A is distributed because “all” is used. | “All” applies only to the subject. The predicate of A is undistributed. |
| In an O proposition, the subject is distributed because the proposition is negative. | Quality decides predicate, not subject. Subject of O is undistributed because the quantity is particular. |
| Distribution depends on the meaning of the term. | Distribution depends only on the form (quantity and quality) of the proposition. |
| An I proposition distributes its predicate because every “is” connects two equal classes. | The “is” of predication asserts only partial overlap. I distributes neither term. |
| “Some” in logic means “only some” / “not all”. | “Some” in logic means “at least one, possibly all”. |
Application: A Quick Decision Procedure
To find the distribution of any proposition, follow these three short steps:
- Reduce the sentence to one of the standard forms A, E, I or O.
- For the subject: ask “Is the proposition universal?” If yes, the subject is distributed; if no, it is undistributed.
- For the predicate: ask “Is the proposition negative?” If yes, the predicate is distributed; if no, it is undistributed.
This three-step procedure works for every standard categorical proposition without exception.
Relation between Distribution and Other Topics
| Topic | Connection with Distribution |
|---|---|
| Conversion | Conversion is valid only when no term is distributed in the converse that was not distributed in the convertend. |
| Obversion | The obverse changes the quality and replaces the predicate with its complement; the new predicate’s distribution follows the rule of the new quality. |
| Contraposition | Performed by combining obversion and conversion, both governed by distribution rules. |
| Categorical Syllogism | Three of the standard rules of syllogism (middle term, distribution of major/minor, total negative premises) are framed in terms of distribution. |
| Square of Opposition | While the square itself shows truth-relations, the underlying mechanism of contradictoriness, contrariety and sub-contrariety can be analysed through distribution patterns. |
Mnemonic to Remember: “Asebino” – A: subject; E: both; I: none; O: predicate. Or simply: Universals distribute subject, Negatives distribute predicate.
This completes the Class 11 Logic and Philosophy Chapter 5 Question Answer | Distribution of Terms | English Medium | ASSEB notes. Mastery of this chapter prepares students for the chapters on inference, categorical syllogism and immediate inference, where the doctrine of distribution is constantly applied.