Illegal considerations are acts, which if done or promises which if enforced, would be prejudicial to the public interest. Har riman, Cont. 101.
Impossible considerations are those which cannot be performed.
Moral considerations are such as are bas ed upon a moral duty.
Past consideration is an act done before the contract is made, and is ordinarily by itself no consideration for a promise; An son, Contr. 82. Pollock considers that whether a past benefit is, in any case, a good consideration is a question not free from uncertainty. On principle it should not be. Possible exceptions might be ser vices rendered on request, without definite promise of reward (see Hob. 105) and vol untarily doing something which one was legally bound to do. Also a promise to pay a debt barred by the statute of limitations ; but he considers that none of these excep tions are logical. See Poll. Contr. 170.
Valuable considerations are either some benefit conferred upon the party by whom the promise is made, or upon a third party at his instance or request ; or some detri ment sustained, at the instance of the party promising, by the party in whose favor the promise is made. Doct. & Stud. 179; Towns ley v. Sumrall, 2 Pet. (U. S.) 182, 7 L. Ed. 386 ; Violett v. Patton, 5 Cra. (U. S.) 142, 3 L. Ed. 61; Wright v. Wright, 1 Litt. (Ky.) 183; Powell v. Brown, 3 Johns. (N. Y.) 100; Brewster v. Silence, 8 N. Y. 207 ; Forster v. Fuller, 6 Mass. 58, 4 Am. Dec. 87 ; Lomas ter v. Burckhart, 2 Bibb (Ky.) 30 ; Woold ridge v. Cates, 2 J. J. Marsh. (Ky.) 222 : Farmer v. Stewart, 2 N. H. 97 ; Shenk v. Mingle, 13 S. & R. (Pa.) 29; Tompkins v. Philips, 12 Ga. 52 ; Odineal v. Barry, 24 Miss. 9; Dunbar v. Bonesteel, 3 Scam. (Ill.) 33; Taylor v. Meek, 4 Blackf. (Ind.) 388; 3 C. B. 321; Hodge v. Powell, 96 N. C. 67, 2 S. E. 182, 60 Am. Rep. 401. The detri ment to the promisee must be a detriment on entering into the contract and not from the breach of it; Ridgway v. Grace, 2 Misc. 293, 21 N. Y. Supp. 934.
"A valuable consideration may consist either in some right, interest, profit, or bene fit accruing to one party, or some forbear ance, detriment, loss, or responsibility giv en, suffered, or undertaken by the other." L. R. 10 Ex. 162. See Train v. Gold, 5 Pick. (Mass.) 380.
A valuable consideration is usually in some way pecuniary, or convertible into money; and a very slight consideration, provided it be valuable and free from fraud, will support a contract ; Lawrence v. McCalmont, 2 How. (U. S.) 426, it L. Ed. 326; Phelps v. Stewart, 12 Vt. 259 ; Upson v. Raiford, 29 Ala. 188; Harlan v. Harlan, 20 Pa. 303; Sanborn v. French, 22 N. H. 246; 11 Ad. & E. 983; Mathews v.
Meek, 23 Ohio St. 292. Valuable considerations are divided by the civilians into four classes, which are given, with literal translations: Do ut des (I give that you may give), Pack ut facias (I do that you may do), Facio ut des (I do that you may give), Do ut facias (I give that you may do).
Consideration has been treated as the very life and essence of a contract ; and a parol contract or promise for which there was no consideration could not be enforced at law; Reading R. R. Co. v. Johnson, 7 W. & S. (Pa.) 317 ; Plowd. 308 ; Cumber v. Wane, 1 Smith, Lead. Cas. 606; Mos by v. Leeds, 3 Call (Va.) 439 ; Cook v. Bradley, 7 Conn. 57, 18 Am. Dec. 79 ; Brown v. Adams, 1 Stew. (Ala.) 51, 18 Am. Dec. 36; Thacher v. Dinsmore, 5 Mass. 301, 4 Am. Dec. 61; Burnet v. Bisco, 4 Johns. (N. Y.) 235 ; Perrine v. Cheeseman, 11 N. J. L. 174, 19 Am. Dec. 388; Beverleys v. Holmes, 4 Munf. (Va.) 95; Westmoreland v. Walk er, 25 Miss. 76 ; Chase v. Vaughan, 30 Me. 412; Goldsborough v. Gable, 140 269, 29 N. E. 722, 15 L. R. A. 294 ; McNutt v. Loney, 153 Pa. 281, 25 Atl. 1088 ; Bush v. Rawlins, 89 Ga. 117, 14 S. E. 886; North Atchison Bank v. Gay, 114 Mo. 203, 21 S. W. 479 ; Brooke, Abr. Action, sur le Case, 40; such a promise was often termed a nudism pactum (ex nudo pacto non oritur actio), or nude pact., This phrase was un doubtedly borrowed from the Roman law, but its use in English law had no relation whatever to its meaning in the Roman ; nor is the word pact of the latter in any sense related to the common-law contract. The mudum pactum, as appears by the note cited infra from Pollock, had not anciently in England its modern signification of an agree ment without consideration in the sense of the maxim quoted. In an elaborate note to Pollock, Contracts 673, the learned author calls attention to a difference between con sideration in the English law and its near est continental analogies, which difference, he says, has not always been realized. The actual history of the English doctrine is ob scure. The most we can affirm is that the general idea was formed somewhere in the latter part of the fifteenth century. At the same time or a little later, nudism pactum lost its ancient meaning (viz.: an agree ment not made by specialty so as to support an action of covenant or falling within one of certain classes so as to support an ac tion of debt), and came to mean what it does now. The word consideration in the sense now before us came into use, at least as a settled term of art, still later. In the early writers, consideration always means the judgment of a court.