A Maxim of Law is universally held truth considered so basic as to be automatically understood. They are very powerful both in Law and at Law (Lawful vs. Legal). There are too many to fully list, but many of the basic ones are listed here and more will be indexed as they arise in the course of filing information on this site. These are presented along with Case Law citation as proof of validity.
"Laws cannot prevent accidents, nor can a law equally protect all against them. (Louisiana v. Resweber 329 U.S. 459, 465) "Mistakes, neglect or misconducts are not to be regarded as accidents." (Citizens Nat. Bank v. Cincinnati 19 Ohio Dec 685, 687) "Not what is said, but what is done, is to be regarded." (Co. Litt. 36; 6 Bingh. 310; Osborn v. Cook, 11 Cush. (Mass) 536) "Environment illuminates the meaning of acts, as context does that of words." (Cramer v. United States 325 U.S. 1, 33) "Certain legal consequences are attached the to the voluntary act of a person." (Duncan v. Landis 106 Fed. 839) "Where there is no act, there can be no force." (4 Coke, 43) "No man ought to be burdened in consequence of another's act." (Kent, Comm. 646) "A repugnant act cannot be brought into being, i.e., cannot be made effectual." (Plowd. 355) "One may not do an act to himself." (Bouv. 146) "An act done by me, against my will, is not my act." (Branch, Princ.; Bract. 101b; Cycl. Dict. 25) "A wise man does every thing advisedly." (4 Inst. 4) "In many counselors there is safety." (4 Inst. 1) "The same person cannot be both agent and patient; i.e., the doer and the person to whom the thing is done." (Jenk. Cent. 40 "He who does a thing by another is considered as doing it himself [i.e. the acts of an agent are the acts of the principal.] (Broom, Max. 817, 818, et seq.; 1 Bl. Comm. 429; Story, Ag. s. 440; Co. Litt. 258; Bouv. Inst. n. 1273; Comm v. Dewitt, 10 Mass. 155) "He who commands a thing to be done is held to have done it himself." (Story, Balim. s. 147) "Whatever things or right that are acquired by an agent are acquired for his principal." (Story Ag. s. 403) "An agreement induced by fraud cannot stand." (Dig. 2, 14, 7, s. 9) "Those thing which are impossible to be given, or which are not in the nature of things, are regarded as no part of an agreement." (Dig 50, 17, 135) (Licensing) "By special agreement, things are allowed which are not otherwise permitted." (Co. Litt. 166) "The expressed agreement of the parties overcomes or prevails against the law, because the agreement of the parties makes the law of the contract." (Story Ag. s. 368; Dig. 16, 3, 1, 6; 2 Coke, 73) "A naked agreement [i.e. without consideration] does not beget an obligation." (Dig. 2, 14, 7, 4; Broom, Max. 746) "It is a wretched state of things when law is vague and mutable." (2 Salk. 512) "In ambiguous expressions, the intention of the person using them is to be chiefly regarded." (Dig. 50, 17, 96; Broom, Max. 567) "It matters not whether a revocation be by words or by acts." (Cro. Car. 49; Branch, Princ) "It is a liberty of free citizens to retain arms for their protection and according to their condition." (People v. Horton 264 N.Y.S 84, 88) "The people have a right to bear arms for the defense of themselves and the state." (An American Maxim) "An attempt does not harm unless a consequence follow." (11 Coke, 98. Cycl. Dict. 700) "An attempt is an intent to do a particular criminal thing with an act toward it falling short of the thing intended." (State v. Davis 229, A.2d 842, 844, 108 N.H. 158) "A delegated power cannot again be delegated." (2 Inst. 597; Black's 2d. 347; 2 Bouv. Inst. n. 1300.) "A deputy cannot have (or appoint) a deputy." (Story, Ag. s. 13; 9 Coke, 77; Bouv. Inst. n. 1936) "A derivative power cannot be greater than the original from which it is derived." (Noy Max.; Wing, Max. 66; Finch Law, b. 1, c. 3.) "Nothing is so becoming of authority as to live in accordance with the laws." (Fleta, lib. 1, c. 17, s. 11.) "Where there is no authority to establish a rule, there is no necessity to obey it." ( Black's 2d. 1181; Dav. Ir. K.B. 69.) "Useless power is to no purpose." (Branch, Princ.) "An equal has no power over an equal." (Jenk. Cent. 174. (One of two judges cannot commit the other for contempt.)) "Power should follow justice, not go before it." (3 Bulst. 199; 2 Inst. 454.) "One lawfully commanding must be obeyed." (Jenk. Cent. 120) "Power is not synonymous with a right." (Poe v. Seaborn, 282 U.S. 101, 113.) "In the presence of the superior power, the inferior power ceases. (Jenk. Cent. 214, c. 53; 13 How (54 U.S.) 142.) "The less authority is merged with the greater." (Broom, Max. 111.) "A benefit is not conferred on one who is unwilling to receive it; that is to say, no one can be compelled to accept a benefit against his consent." (Dig 50, 17, 69; Broom, Max. 699, note. "He who receives the advantage or benefit from a thing should also bear the burden or disadvantages attending it." (1 Coke, 99; Broom, Max. 706-713; 1 Kames, Eq. 289; 2 Bouv. Inst. n. 1433; 1 Story, Const. 78.) "What I approve I cannot reject. I cannot approve and reject at the same time. I cannot take the benefit of an instrument, and at the same time, repudiate it." (Broom, Max. 712.) "To sell is one thing, to consent to sale is another thing." (Dig. 50, 17, 160.) "Remove the cause and the effect will cease." (2 Bl. Comm. 203.) "Where the law is uncertain, there is no law." (Black's 1181; Bouv. 160) " A clause in law which precludes its abrogation is void from the beginning.) (Bacon, Max. reg 19; Broom, Max. 3d Lond. ed. 27.) "Names of things ought to be understood according to common usage, not according to the opinions of individuals." (Dig. 33. 10. 7. 2.) "Things derogatory to the common law are not to be drawn into precedent." (Branch, Princ.) "He may consent tacitly who may consent expressly." (Dig 50, 17, 3.) "He who does not forbid what he can forbid, seems to assent." (2 Inst. 308; 8 Exch. 304; 1 Bl. Comm. 430.) "Nothing is so contrary to consent as force and fear." (Dig 50, 17, 116.) He who consents cannot receive injury." (Broom, Max. 268, 269, 271, 395; Wing. Max. 482; 2 Bouv. Inst. n. 2279; Plowd. 501.) "The silence of a party implies his consent, when his interest is at stake." (Jenk. Cent. p. 32, case 64; Broom, Max. 138, 787; 9 Mod. 38.) "He who does not disapprove when he can approves." (3 Inst. 27.) "A contract without consideration, or upon false consideration, (which fails,) or upon unlawful consideration, cannot have any effect. (Code. 3, 3, 4; Chit. Cont. (11th Am. Ed.) 25, note; Noy, Max. 24; 2 Bl. Comm. 445; 1 Story, Contr. s. 525.)