have suffered from your failure to carry out the bargain. It is your fault that it has not been carried out." But the seller's claim for instalments of the price can only be justified on the assumption that he does not propose to take advantage of Ms right to refuse to go on with the contract. If the seller recovers the price, the buyer must be entitled to the land." There is no use in allowing the seller to recover even a single instalment of the price when all have become due unless the contract is to be fully performed, for recovering even one instalment will operate as an election by the vendor to proceed with the contract despite any default which has thus far occurred.71 If then the contract is to be fully performed, the time has come for performance, and it should be full performance. All the price ought to be paid, and the land ought to be conveyed. This rule is recognized in equity where a decree for specific performance is made after the several performances under a contract have become due, though originally performable at different times,72 and the rule at law should be the same; except that since it is impossible to protect the defendant by making the decree against him conditional on the plaintiff's simultaneous performance, the plaintiff must tender performance before action. § 888. Aleatory contracts. Since the basis of excusing one party to a bilateral contract from liability because of default in the performance of the counter promise, is the assumption that not only are the two promises in exchange for one another, but that each performance is intended as the price or equivalent of the other, a type of contract where this assumption does not hold good 70 See supra, § 791, ad fin. 71 See Manning v. Brown, 10 Me. 49. The statement in regard to even a payment of interest made in Eastern Oregon Land Co. v. Moody, 198 Fed. 7, 27, 119 C. C. A. 135, by Gilbert, J., diss. seems accurate. "The acceptance of a payment on account of interest was wholly inconsistent with an intention to rescind the contract under the notice of August 11th. It was an acknowledgment of the continued existence of the contract. It was the acceptance of a benefit thereunder-the acceptance of an instalment, in disaffirmance of a prior notice that had called for the payment of the whole sum due" [by a certain time which had elapsed]. 72 Hunter v. Daniel, 4 Hare, 420. must be dealt with in a different way. "Whenever the performance of mutual covenants or promises are unequal in certainty, they will also be unequal in amount," 73 and must have been so regarded by the parties. In an aleatory contract, therefore, unless each promise is subject to the same risk, it is obvious that the performances were not contracted for as equivalent to one another. The premium of insurance is not assumed to be equivalent to the face of the policy. The premium is paid for the risk, and risk is but another name for a binding obligation to pay upon a contingency. That is, the premium is the exchange for the promise, not for the performance of it.74 Insurance policies are not usually bilateral, but not infrequently a promissory note is accepted for the premium. In such a case each party is under an executory obligation, but breach of the obligation by the insured will not excuse subsequent non-performance by the insurer.75 The propriety of such decisions is obvious upon reflection. If the insured made default in payment of the note for the premium, it is clear that the insurer might, and would, if the premises were not burned during the term of the insurance, sue and recover the amount of the note. It cannot be permitted for the insurer to have the option of refusing to pay the insurance if the premises are destroyed, asserting as an excuse the non-payment of the premium (unless indeed the payment of the note is made an express condition precedent of the insurer's liability) and, at the same time, be entitled to demand payment of the premium note if the contingency of fire does not occur. A contract to guarantee is similar in principle. A bilateral contract may be aleatory on one side only, as in the case of insurance in return for a promised premium; or, it may be aleatory on both sides, as where one promisor guarantees 73 Langd. Summ. Cont., § 107. 74 In Perlee v. Jeffcott, 89 N. J. L. 34, 97 Atl. 789, speaking of a payment made for an option, the court said: "The consideration in a legal sense was Perlee's promise to keep the offer to sell open for a year. It was the promise, not the performance." 75 McMahon v. United States Life Ins. Co., 128 Fed. 388, 63 C. C. A. 130, 68 L. R. A. 87; Mutual Life Ins. Co. v. French, 30 Oh. St. 240, 27 Am. St. Rep. 443; Alexander v. Continental Ins. Co., 67 Wis. 422, 30 N. W. 727. See also Big Run Coal Co. v. Employers' Indemnity Co., 163 Ky. 596, 174 S. W. 25. a debt due his promisee in return for a guarantee of another debt due to himself.76 A distinction must be observed where the contingency upon which the performance of an aleatory promise depends is identical with the contingency upon which performance of the counter promise depends. In such a case since one performance will fall due, according to the terms of the contract, in every case where the other also falls due, the general principle in bilateral contracts of assumed equivalence of the performances on each side is applicable. Where a buyer promises to pay a thousand dollars for a horse if it wins a race, but otherwise nothing, in return for the promise of the seller to transfer title to the horse whether it wins the race or not, it is obvious that one thousand dollars is not assumed by the parties as the value or equivalent of the horse either then or after the race. As the seller will get nothing for the horse if the race is lost, it must be assumed that the money payable if the race is won, will exceed the value of the horse by an amount sufficient to compensate the seller for his risk of getting nothing. On the other hand, if the buyer promises to buy the horse if it wins the race, and pay a thousand dollars for him, while the seller promises to transfer title only in the event that the horse wins the race, it is evidently assumed by the parties that the price named is the equivalent of the horse in case any sale is made. In other words, the risk in such an aleatory contract, as that last supposed, relates to the question whether a mutual exchange shall take place. damages in respect of the breach on one side must be very different from the damages arising from the breach on the other side; on the one side they would be 300l. and on the other only 1621.; it is consequently apparent, on the face of the contract itself, that it was not intended by the parties that performance of the one stipulation should be a condition precedent to performance of the other." See also Gibson v. Goldsmid, 5 DeG. M. & G. 757; Perlee v. Jeffcott, 89 N. J. L. 34, 97 Atl. 789; cf. Blair-Baker Horse Co. v. Hennessey, 36 R. I. 132, 89 Atl. 299. If the contingency occurs, there is to be an exchange, and the performances will be mutually dependent.” § 889. When performances in bilateral contracts are in exchange for one another. It has been suggested that one who enters into any promise is in effect taking a risk analogous to the risk of an insurer or guarantor. Something must come to pass or the promisor will be liable in damages. If this were true, it might be urged that one who gave consideration for a promise was always simply buying a chance, and that in every case the promises should be regarded as independent or at least that the parties by putting the transaction in appropriate words, might produce this result. If it be conceded that promises to buy and sell a horse for $500 involved an agreement to exchange as equivalent performances the horse and the price, it may be argued that if the buyer promises to pay $500, not for the horse, but in return for a promise by the seller to pay damages if he does not transfer the horse, or if the horse is not transferred, the contract is an aleatory one. But the matter does not depend wholly on question of form. It is a question of fact, whether $500 was the price of the horse; and just as parties cannot transform a conditional sale into a lease, simply by calling it such 78 so they cannot deceive a tribunal by the mere form of language. § 890. Covenants in leases are independent. An ordinary lease is a partly bilateral contract. The main part of the consideration furnished by the lessor is furnished by him when the lease is made. At this time he conveys to the lessee an estate for years. The lessor, however, ordinarily makes executory covenants besides. On the part of the lessee the consideration is wholly executory, consisting of covenants to pay rent and render such other performance as the lease requires of him. As an original question a lease might well have been regarded as a wholly bilateral agreement by which the lessor instead of making a conveyance, promises a con "Cases of this sort are Griggs v. Moors, 168 Mass. 354, 47 N. E. 128; Martin v. Schoenberger, 8 W. & S. 367. 78 See Williston, Sales, § 336. tinuing permission to occupy the premises. This is the way in which a lease is regarded in the Civil Law.79 If it were thus regarded there would seem no reason why the principles of dependency applicable to ordinary bilateral contracts should not likewise be applicable to leases. In fact they are not thus applicable in English and American law. Partly because a lease is regarded primarily as a conveyance by the common law, partly because the law governing leases has been dealt with in connection with the law of real estate, and became settled before the law of mutually dependent promises was established, and partly no doubt because leases have ordinarily been elaborately written documents in which the parties might be supposed to have expressed their intent with considerable fullness, covenants in leases have been held mutually independent unless in terms expressly conditional. Thus the breach on the part of a landlord of a covenant to repair, does not excuse the tenant from liability on his covenant to pay rent.81 Nor does destruction of the leased prem 79 See Viterbo v. Friedlander, 120 U. S. 707, 30 L. ed. 776, 7 S. Ct. 962. 80 Powell v. Merrill, (Vt. 1918), 103 Atl. 259, 261, and see cases in the following note. Occasionally a decision is found where a lease is treated like an ordinary bilateral contract, and as an original question this method of treatment has much to commend it. Berman v. Shelby, 93 Ark. 472, 125 S. W. 124. In University Club v. Deakin, 265 Ill. 257, 106 N. E. 790, 791, 1915 C. 854, the court said that it was rightly ruled "at the request of plaintiff in error, that the lease sued upon was a bilateral contract, and upon a breach of an essential covenant thereof by the lessor the lessee had a right to refuse further to be bound by its terms and to surrender possession of the premises, and that a breach of the twelfth clause of the lease [in which the landlord agreed not to lease other shops in his building to any one conducting the same business as the lessee] would be a good defence to an action for rent if the tenant surrendered possession of the premises within a reasonable time after discovery of the breach." Cf. Rubens v. Hill, 213 Ill. 523, 72 N. E. 1127. In In re Mullings Clothing Co., 238 Fed. 58, 151 C. C. A. 134, L. R. A. 1918 A. 539, 252 Fed. 667, the discussion by the court seems to indicate the assumption that a lease is an ordinary bilateral contract. 81 Belfour v. Weston, 1 T. R. 310; Dawson v. Dyer, 5 B. & Ad. 584; Suplice v. Farnsworth, 7 M. & G. 576; Edge v. Boileau, 16 Q. B. D. 117, 120; Tedstrom v. Puddephat, 99 Ark. 193, 137 S. W. 816; Arnold v. Krigbaum, 169 Cal. 143, 146 Pac. 423; Lewis v. Chisholm, 68 Ga. 40; Palmer v. Meriden Britannia Co., 188 III. 508, 59 N. E. 247; Rubens v. Hill, 213 Ill. 523, 72 N. E. 1127; Harthill v. Cooke's Ex., 19 Ky. L. Rep. 1524, 43 S. W. 705; Leavitt v. Fletcher, 10 Allen, 119; Taylor v. Finnegan, 189 Mass. 568, 575, 76 N. E. 203, 2 L. R. A. (N. S.) 973; Meredith Mech. Assoc. v. Amer |