Predication and the Copula
Chapter Thirty-Nine
Syllabus topic 2.10, "Meaning of predication with special reference to the copula."
Pages 188 to 192 of 334
In one line
Predication is the act of asserting something of something, and the copula is the word that carries that assertion.
In the wording a student can write in an examination: predication is the joining of a predicate to a subject in an assertion; the copula is the sign of that joining, expressed in English by "is", "are", "is not" and "are not". The copula carries the quality of the proposition and asserts a relation, not a time.
What predication is
Every categorical proposition does one thing: it takes something and says something about it. The something is the subject; the something said is the predicate; the saying is predication.
That is not as empty as it sounds, because two things follow immediately.
Predication is an assertion and not a naming. "The registered document" names something and asserts nothing. "The document is registered" predicates registration of the document, and is therefore true or false. This is why a term is not a proposition, at sequence 170, and it is the whole difference.
Predication is what the copula performs. Remove the copula and there is no assertion left, only two terms lying side by side.
The copula and its three functions
It joins. The copula is what makes two terms into one proposition. This is the function it is named for: copula is Latin for a link.
It carries the quality. Affirmative or negative is settled in the copula and nowhere else. "Is" affirms and "is not" denies, and reduction to logical form, at sequence 300, requires any negative to be brought into the copula.
It asserts. The copula is the sign that the speaker is committing themselves. In a conditional, where nothing is asserted, the copulas of the antecedent and consequent are present but the whole is not asserted, which is why sequence 290 insisted that a conditional asserts neither part.
What the copula is not
It is not a term. It is syncategorematic, as sequence 170 established: it has no meaning standing alone and can be neither subject nor predicate. A student who counts three terms in "All contracts are agreements" has counted the copula as one.
It does not assert existence. "Is" in the copula is not the "is" of existence. This is the point that connects to the last chapter: reading the copula as an assertion of existence is precisely what gives universal propositions their traditional existential import, and it is what the modern scheme rejects.
Above all, it does not indicate time. This is the point MU's phrase "with special reference to the copula" is pointing at, and it deserves its own section.
The copula is timeless
The copula is always written in the present tense and it never means the present time.
Predication and the Copula
"Aristotle is a Greek philosopher" does not assert that Aristotle is alive. "The accused is a person who struck the deceased on 4 April 2019" does not assert that the striking is going on now. The present tense of the copula is a grammatical convention, and what it expresses is a relation between the subject and the predicate, not a moment.
How time is expressed instead. Time goes into the terms, not into the copula. "The notice was served in March" becomes, in logical form, "the notice is a thing served in March", where the whole of the temporal information sits inside the predicate term. This is the device already used at sequence 300 for propositions about frequency, and it is the same device applied to tense.
Why it matters. Because inference in Module III operates on the copula, and every operation there, conversion, obversion, contraposition, assumes that the copula is a plain timeless link. A student who thinks the copula carries tense will produce nonsense at the first obversion.
The four things the English "is" does
English uses one word for four different jobs, and telling them apart is a standard examination question in this topic. Only the first is the copula.
The "is" of predication, the copula proper. "The document is registered." A quality is asserted of a thing.
The "is" of class membership. "Ravi is a lawyer." An individual is placed in a class. Traditional logic treats this as predication too, which is one of the places the modern scheme separates what the older one ran together, at sequence 340.
The "is" of identity. "The Managing Director is the person who signed the guarantee." Here the two sides name the same individual, and the proposition can be read in either direction, which no ordinary predication can. Identity statements are the reason some logics need a special sign for identity.
The "is" of existence. "There is a contract between the parties." Nothing is being predicated of anything; the claim is that something exists. This is failure five at sequence 320, and it is why the modern scheme uses a quantifier for existence rather than a predicate.
A worked distinction. "The tenant is the occupier" may be any of three of these. If it means that the tenant has the quality of occupying, it is predication. If it means that the tenant belongs to the class of occupiers, it is class membership. If it means that the person called the tenant and the person called the occupier are the same person, it is identity. In a dispute about who is liable to be evicted, the three readings lead to different results, and only the third supports the inference that anything true of the occupier is true of the tenant.
Predication and the Copula
A worked example
A section provides: "A person is said to be an insider if he is or has been connected with the company."
Find the copulas. There are three "is" or "has been" constructions and they are not doing the same work.
"A person is said to be an insider" is a stipulative definition: the statute is laying down that the word "insider" shall apply. It is not an ordinary predication at all but an act of definition, which is Module IV's subject at sequence 570.
"if he is connected with the company" is a predication with a relational predicate, and the "is" here is the copula proper.
"or has been connected" is the same predication with the time shifted, and the shift is carried by the verb and not by the copula. In logical form the two together become one predicate: "x is a person who is or has at any time been connected with the company". The whole of the temporal range sits inside the term.
What the analysis shows. The definition covers past connection as well as present, and once the temporal words are inside the term, the proposition is timeless and the ordinary operations of Module III can be performed on it. Anyone who left "has been" outside the term would find that obversion produced something meaningless.
Distinctions that carry marks
| Function of the copula | What it does |
|---|---|
| Joining | Makes two terms into one proposition |
| Quality | Carries affirmative or negative |
| Assertion | Signals that the speaker commits to the proposition |
| Use of the English "is" | Example | Logical treatment |
|---|---|---|
| Predication | The document is registered | The copula proper |
| Class membership | Ravi is a lawyer | An individual placed in a class |
| Identity | The Managing Director is the signatory | The two sides name one thing; reversible |
| Existence | There is a contract | Not predication; a quantifier in modern logic |
| The copula | Tense | |
|---|---|---|
| Expresses | A relation between subject and predicate | Nothing; the copula is timeless |
| Where time goes | Not here | Into the predicate term |
| Consequence | Module III operates on a plain link | Temporal words must be absorbed before inferring |
What this does not mean
The copula is not the verb of the sentence. "The tenant occupies the premises" has no copula on its face; reduced to logical form it becomes "the tenant is a person who occupies the premises", and the copula appears.
The copula does not assert existence, and reading it as though it did is what produces the traditional doctrine of existential import.
Predication is not the same as description. A description names; a predication asserts. The difference is the presence of a copula doing its third job.
Predication and the Copula
Quick revision
Predication: asserting a predicate of a subject. Copula: the sign that joins them.
Three functions of the copula: joining, carrying quality, asserting.
The copula is timeless. Its present tense is a convention, and time is expressed by putting temporal words inside the predicate term.
The copula is syncategorematic: not a term, and not to be counted among the terms of a proposition.
Four uses of the English "is": predication, class membership, identity, existence. Only the first is the copula.
Why it matters: every operation in Module III works on the copula, and treating it as tensed or as existential breaks all of them.
Test yourself
1. What is predication, and what is the copula?
Predication is the act of asserting a predicate of a subject, that is, of saying something about something. The copula is the sign of that joining, expressed in English by "is", "are", "is not" and "are not". Remove the copula and no assertion remains, only two terms placed side by side, which is why a term is not a proposition.
2. State the three functions of the copula.
It joins the subject term to the predicate term, making one proposition out of two terms. It carries the quality of the proposition, affirming or denying, which is why reduction to logical form requires any negative to be brought into it. And it asserts, signalling that the speaker commits to the proposition, which is why a conditional, whose parts contain copulas, asserts neither of them.
3. Why is the copula said to be timeless, and where does time go instead?
Because its present tense is a grammatical convention and expresses a relation rather than a moment: "Aristotle is a Greek philosopher" does not assert that Aristotle is alive. Time is expressed by absorbing the temporal words into the predicate term, so that "the notice was served in March" becomes "the notice is a thing served in March". This is necessary because every operation in Module III assumes a plain, timeless link.
4. Distinguish the four uses of the English "is".
The "is" of predication asserts a quality of a thing and is the copula proper. The "is" of class membership places an individual in a class. The "is" of identity says that the expressions on either side name the same individual, and is reversible in a way no ordinary predication is. The "is" of existence asserts that something exists and predicates nothing of anything, which is why modern logic uses a quantifier for it.
5. Why does the copula not assert existence?
Because its function is to link a subject to a predicate, not to claim that the subject has instances. Reading it as an assertion of existence is exactly what gives the traditional universal its existential import, and produces the result that "all trespassers will be prosecuted" asserts that there are trespassers. The modern scheme keeps the two apart by using a separate quantifier for existence.
Predication and the Copula
6. Reduce "The tenant occupies the premises" to logical form and identify the copula.
It becomes "The tenant is a person who occupies the premises". The copula is "is", and it did not appear in the original sentence, whose verb was "occupies". This shows that the copula is not the verb of the sentence: it appears when the sentence is put into standard form, with the whole of the assertion about occupation absorbed into the predicate term.
The rest of this subject
These notes are cut from the University's printed syllabus. Open the syllabus itself, or the past papers, for the same subject.