Express and Implied Promises under Section 9 of the Indian Contract Act, 1872: Acceptance by Conduct, Why Silence Is Not Acceptance and Why Mental Assent Is Insufficient

Section 9 draws a line through the middle of the law of acceptance. A promise made in words is express; a promise made otherwise than in words is implied. The section tells us that assent may be signified by conduct, and it is the statutory basis of most of the contracts people make in daily life without saying anything at all. But conduct is not the same as inaction. Two propositions sit on the far side of the line and are the subject of most of the litigation: silence does not ordinarily amount to acceptance, and an acceptance formed in the mind but never signified is legally nothing. This topic works through all three.

1. Section 9 and the Basis of Implied Promises

Sections 9, 3 and 2(b), Indian Contract Act, 1872

9. Promises, express and implied. In so far as the proposal or acceptance of any promise is made in words, the promise is said to be express. In so far as such proposal or acceptance is made otherwise than in words, the promise is said to be implied.

3. The communication of proposals, the acceptance of proposals, and the revocation of proposals and acceptances, respectively, are deemed to be made by any act or omission of the party proposing, accepting or revoking, by which he intends to communicate such proposal, acceptance or revocation, or which has the effect of communicating it.

2(b). When the person to whom the proposal is made signifies his assent thereto, the proposal is said to be accepted.

Three points about the drafting deserve notice. First, Section 9 uses the words in so far as, which means the classification operates term by term and not contract by contract: a single contract may be partly express and partly implied, as where price is agreed in words and delivery is settled by the parties' established practice. Second, the legal effect of the two is identical; an implied promise is as binding as an express one, and the distinction goes to proof rather than to force. Third, Section 3 supplies the mechanism, since it treats any act which has the effect of communicating as a communication.

1.1 Where implied promises are found

Conduct at the point of transacting. Boarding a bus, taking an article from a shelf to the counter, stepping into a taxi, or inserting money into a vending machine.
Accepting and using what has been supplied. Receiving goods and dealing with them as one's own, or occupying premises and paying for the occupation.
A course of dealing between the parties. Where the parties have contracted repeatedly on the same terms, those terms may be implied into a later transaction concluded without express reference to them.
Trade usage. Preserved by the saving in Section 1, and capable of supplying terms the parties did not state.
Professional services rendered and accepted. A person who consults a professional without discussing fees impliedly promises to pay a reasonable remuneration.

2. Acceptance by Conduct

The clearest illustration of Section 9 is the case where the parties never conclude their negotiations in words but proceed to act on the terms under discussion. The law does not require them to go back and perform the ritual of offer and acceptance; it finds the acceptance in what they did.

📖 Brogden v. Metropolitan Railway Co., (1877) 2 App Cas 666 (HL)

Facts: A colliery owner had supplied coal to a railway company for years without a formal contract. The parties decided to regularise the arrangement. The company's agent sent a draft agreement; Brogden filled in the name of an arbitrator, marked it approved, and returned it. The company's agent put it in his drawer and nothing further was done about it. Both parties then supplied and took coal on its terms for two years. A dispute arose and Brogden denied that there was any contract.

Held: The House of Lords held that there was a binding contract on the terms of the draft. Brogden's return of the document with the arbitrator's name inserted was a counter offer, and the company accepted it by conduct, namely by ordering and accepting coal on those terms. Acceptance need not be signified in words where the parties' course of dealing shows unmistakably that both regarded themselves as bound.

Ratio: An offer may be accepted by conduct. Where parties act on the terms of a document each has treated as governing their dealings, the court will find a concluded contract on those terms notwithstanding that no formal acceptance was ever communicated.

The Indian application of the same principle appears in Haji Mohammed Ishaq v. Mohd. Iqbal, (1978) 1 SCC 564, where goods were received and dealt with and payments were made, and the Supreme Court inferred a contract between supplier and recipient although nothing had passed between them in words.

3. Silence Is Not Acceptance

Conduct signifies assent; silence, standing alone, signifies nothing. The rule follows directly from Section 2(b), which requires the offeree to signify his assent. An offeror who stipulates that he will treat silence as acceptance is attempting to manufacture the offeree's signification out of the offeree's inaction, and he cannot do so.

📖 Felthouse v. Bindley, (1862) 11 CB NS 869

Facts: An uncle negotiated with his nephew for the purchase of a horse. There had been a misunderstanding about the price, and the uncle wrote saying that if he heard no more about the horse he would consider it his at a stated figure. The nephew did not reply, but told the auctioneer selling his farming stock to keep the horse out of the sale. The auctioneer sold it by mistake, and the uncle sued the auctioneer in conversion, which required him to show that the horse was already his.

Held: The court held that the uncle had no title, because there had been no acceptance. The nephew's intention to sell was never communicated to the uncle, and the uncle could not impose on the nephew a duty to write in order to reject. The instruction to the auctioneer was a dealing with a third party and not a signification of assent to the offeror.

Ratio: An offeror cannot stipulate that silence shall constitute acceptance. Assent must be signified to the offeror, and an uncommunicated intention to accept, however clear, does not conclude a contract.

3.1 Two qualifications

The rule protects the offeree, not the offeror. It exists to prevent an offeror from forcing a contract on a person who has done nothing. It does not follow that an offeree who has stayed silent can never be bound: if he has also acted on the offer, the acceptance is found in the act, and Felthouse turned on the absence of any communication to the offeror rather than on silence as such.
A course of dealing may change the position. Where the parties have established a practice under which orders are performed without acknowledgment, silence followed by performance may be acceptance. What is doing the work in such a case is the course of dealing, not the silence.

⚠ Unsolicited goods and deemed consent

The practical modern application of Felthouse is that a person who receives goods or services he never asked for, accompanied by a demand for payment unless he returns them, is under no obligation to pay and no duty to return. The same reasoning applies to a negative option clause in a subscription, under which continued silence is said to renew the arrangement on new terms. Such a clause binds only if the customer agreed to that mechanism when he originally contracted; it cannot be introduced unilaterally afterwards.

4. Mental Acceptance Is Insufficient

A decision to accept, taken and kept to oneself, is not an acceptance. Section 2(b) requires the offeree to signify assent, and Section 3 requires an act or omission by which he intends to communicate or which has the effect of communicating. A resolution formed in the mind satisfies neither. Three consequences follow.

The offeror may revoke in the meantime. Under Section 5 a proposal may be revoked at any time before the communication of its acceptance is complete as against the proposer. Since a mental acceptance is not put in any course of transmission, the proposer's right to revoke remains intact.
An acceptance written but not sent is equally ineffective. A letter of acceptance drafted and left in a drawer has not been put in a course of transmission, so nothing has happened for the purposes of Section 4.
Communication to a stranger is not communication to the offeror. Telling a third party that one accepts, as the nephew in effect did in Felthouse, does not signify assent to the person who made the proposal, unless that person is the offeror's authorised agent for receiving it.

4.1 The exception in Section 8

The requirement of communication is dispensed with, by implication, where the proposal invites an act rather than a promise. Section 8 provides that performance of the conditions of a proposal is an acceptance of the proposal. Even here the offeree must do something; what is dispensed with is prior notification, not the requirement of an outward act. A person who merely resolves to search for the missing property has accepted nothing.

5. The Three Positions Compared

Conduct of the offeree	Is there acceptance?	Provision and reason
Says yes in words, spoken or written	Yes, an express acceptance	Section 9, first limb; assent is signified in words
Acts on the terms proposed, so that the act conveys assent to the offeror	Yes, an implied acceptance	Sections 9 and 3; the act has the effect of communicating assent
Performs the conditions of a proposal that invited an act	Yes, and no prior notification is needed	Section 8; the offeror has prescribed performance as the manner of acceptance
Does nothing at all, the offeror having said that silence will be treated as acceptance	No	Section 2(b); the offeror cannot supply the offeree's signification, per Felthouse
Decides to accept but communicates nothing to anyone	No	Sections 2(b) and 3; assent must be signified, and the offer remains revocable under Section 5
Tells a third party that he accepts, but not the offeror	No	Assent must be signified to the offeror or to his authorised agent

6. The Position Stated Shortly

Section 9 classifies a promise as express where the proposal or acceptance is made in words, and implied where it is made otherwise than in words.
The words 'in so far as' allow a single contract to be partly express and partly implied, and the legal effect of the two is the same.
Section 3 supplies the mechanism by treating any act or omission which has the effect of communicating as a communication.
Brogden v. Metropolitan Railway: an offer may be accepted by conduct, and parties who act on the terms of a document are bound by it.
Felthouse v. Bindley: an offeror cannot stipulate that silence amounts to acceptance, and an uncommunicated intention does not conclude a contract.
The silence rule protects the offeree; an offeree who has also acted may be bound, and a course of dealing may alter the position.
A person sent unsolicited goods is under no duty to pay or to return them.
Mental acceptance is insufficient, and so is an acceptance written but not despatched or communicated only to a stranger.
Section 8 dispenses with prior notification where the proposal invites performance, but not with the requirement of an outward act.

7. Related Topics and Provisions

Topic or provision	Connection
Communication, Acceptance and Revocation under Sections 3 to 9	The chapter in which Section 9 sits
General Offer and Performance of the Condition	Section 8 and the dispensing with prior notification
Types of Contracts	Express, implied and quasi-contracts as categories
Acceptance vs Counter Offer	The other way in which a purported acceptance can fail
Section 2(b), Indian Contract Act	The requirement that assent be signified
Section 3, Indian Contract Act	Communication by act or omission
Section 5, Indian Contract Act	Why an uncommunicated acceptance leaves the offer revocable
Section 8, Indian Contract Act	Acceptance by performing the conditions of a proposal
Section 9, Indian Contract Act	Promises express and implied
Sections 68 to 72, Indian Contract Act	Obligations imposed without any promise at all, express or implied