Care must be taken to distinguish illegal consideration from consideration which is merely bad for insufficiency. Consideration of the latter sort will not invalidate a contract, though not of itself sufficient to support a promise. If other consideration exists and there is mutual assent to the bargain, recovery may be had.49
46a Stacy v. Brothers (Conn.), 107 Att 613; Thacker v. Smith, 103 Kan. 641, 175 Pac. 783; Moss v. Cope-lof, 231 Mass. 613, 121 N. £. 508.
47 See Kearney v. Whitehaven Colliery Co.,  1 Q. B. 700; More v. Bonnet 40 Cal. 251, 6 Am. Rep. 621; Siddall v. Clark, 89 Cal. 321, 26 Pac. 829; Hynds v. Hays, 25 Ind. 31; Bishop v. Palmer, 146 Mass. 469, 16 N. E. 299,4 Am. St. Rep. 339; Fishell v. Gray, 60 N. J. L. 5, 37 Atl. 606; Lindsay v. Smith, 78 N. C. 328, 24 Am. Rep. 463, 12 Harv. L. Rev. 424. See also an article by Prof. William P. Rogers, 17 Yale L. Jour. 338. It has been suggested (Wald's Pollock, Contracts [3d ed.], 484), that if A, even before performing himself, elected to sue on B's lawful promise and take judgment upon it alone, this would operate as an assent by A to an agreement to perform hjs promise in return for B's lawful promise, thereby binding both parties. Perhaps A's consent should rather be treated as a question of fact in each case. If not liable on the contract he should be quasi-contractually.
48 Edgar v. Ames, 255 Fed. 835, 167 C. C. A. 163; Achen v. Atchison Ac. Ry. (Kans.), 175 Pac. 980; Huber v. Culp, 46 Okla. 570, 149 Pac. 216.
49 See Pierce v. Pierce, 17 Ind. App. 107; King v. King, 63 Ohio St. 363, 369, 59 N. E. Ill, 52 L. R. A. 157, 81 Am. St. Rep. 635. It is to be observed that the portion of the consideration which is insufficient as such must, nevertheless, be given in order to make the bargain enforceable. Otherwise a bargain would be enforced to which the defendant had never assented.