It has sometimes been suggested that a defect in an acceptance might be "waived " by the offeror.99 If what is meant by this is merely that the offeror may accept a counter-offer by the offeree, which, by reason of delay, or the addition or change of terms failed of being an acceptance of the original offer, no fault can be found; but if, as seems to be the case, the meaning is that the offeror may at his option assert either that there has not been a valid acceptance and hence a contract because of some defect, or that there has been a contract made because he is willing to disregard the defect in the acceptance, and that this option on the part of the offeror may be exercised without communication with the offeree, a vital principle of the law of contracts is violated. Nothing is more fundamental than that in bilateral contracts both parties must be bound, or neither; and that in unilateral contracts, the performance requested must be simultaneous with the creation of any obligation on the part of the promisor. To allow a waiver of a defect of an acceptance is virtually to say that the acceptance is binding on the acceptor, or may be treated as binding by the offeror (which amounts to the same thing) from the time when it is made though the offeror himself is still perfectly free to assert that the acceptance was defective, and though no estoppel forbids the acceptor from showing the true facts. In truth, a defective acceptance can only amount to a counter-offer, and the only way a contract can be formed is by acceptance of the counter-offer in the same way as if it were an original offer.

98 In Cavanaugh v. D. W. Ranlet Co., 229 Mass. 366, 118 N. E. 650, following previous negotiations a memorandum of sale was sent to the buyer which, after stating the terms of the bargain, contained these added words,-"This is a contract and will be considered mutually binding unless we are advised of its nonacceptance by wire." The court said of this memorandum " it did not purport to confirm a previous contract; it is of itself an offer to sell, which upon acceptance by the offerees, would become a binding sale ... It could not be ruled as matter of law that if the 'confirma-tion' were treated as an offer, it became a binding agreement from the failure of the plaintiffs to reply. The jury, under all the circumstances, were to say whether the plaintiffs' silence amounted to an assent." The Swiss Code of Obligations provides (Art. 6): "When the offeror ought not reasonably, whether from the particular nature of the transaction or from circumstances, to expect an express acceptance, the contract is deemed concluded if the offer has not been refused within a reasonable time." See also Van Arsdale Brokerage Co. v. Robertson, 36 Okl. 123, 128 Pac. 107.

99 Wheeler v. Klaholt, 178 Mass. 141, 59 N. E. 756. See also Shaenfield v. Hall Safe etc. Co. (Tex. Civ. App.), 157 S. W. 462.