Short sayings in which principles of law of wide application are laid down. They are known to all systems of jurisprudence: thus, "Casus nocet domino" and "Ignorantia juris nocet" are maxims of Roman law; "Nobody can plead his own wrong" and "You can not come into a court of equity but with clean hands" are maxims of English law. Of the maxims which are current in the Talmud many belong to substantive law, others to the law of evidence and procedure. The following may be cited as examples:
- ("I am bound to make good any damage caused by whatever I am bound to guard" [B. Ḳ. i. 2]). This applies to domestic animals, to a pit or any similar source of danger, and to fire. See Accident.
- ("A man is always forewarned" [B. Ḳ. ii. 6]); that is, a man is, like the owner of a "forewarned ox," always liable for the whole damage arising directly from his acts.
- ("A deaf man, a fool, and a child are bad to meet" [B. Ḳ. 87a]) because whoever harms them is liable for the damage done, while no compensation is recoverable from them for any damage done by them.
- ("A man's agent is, in effect, the man himself"). This is similar to the Roman principle "Qui facit per alium facit per se."
- ("Who pays is not flogged" [Mak. i. 2]); that is, wherever the law orders compensation paid for an unlawful act, and the payment is made, punishment by stripes can not be inflicted.
- ("Whenever one thing is more nearly permanent than another it has the preference" [Hor. iii. 6]) appears in the Gemara simply as ("The permanent ranks first"), a rule derived from the often reiterated insistence of the Torah on the celebration of the daily sacrifice on festive days, when other sacrifices also are prescribed
- ("They have no mercy in judgment" [Ket. ix. 2-3]) means that the courts do not act on the principle of modern equity known as "marshaling the assets," the principle of giving to the creditor having the weakest hold on other funds () a stronger hold on the fund under dispute; every creditor must take his chance, according to the opinion of R. Akiba, which prevails over that of R. Ṭarfon.
- ("Damage by seeing is called damage" [Gemara; B. B. 2b]) expresses the right of a householder to privacy; that is, to be screened while in his house or courtyard from the view of his neighbors is a legal right.
- ("One court does not overrule the decision of another court unless it is greater in wisdom and numbers" ['Eduy. i. 5]) is a principle that, supplemented by the high regard in which the Tannaim (ending with R. Judah about 220) were held by succeeding generations, has done much to keep Jewish laws and customs in their old, sometimes obsolete, forms. See Aḥaronim.
- ("Let the judgment pierce the mountain" [Sanh. 6a, b]), corresponding to the Latin "Fiat justitia, ruat cœlum" (Let justice be done though the heavens fall), expresses a principle not much followed in practise, as the sages always desired a compromise between the litigants more than strict enforcement of the law.
- ("No man can make himself out wicked" [Sanh. 25a]) means that no penalty, such as death, exile, or stripes, nor more than full restitution, nor even a fixed sum as damages to an injured party, can be awarded upon the admission or confession of the accused (see Accusatory and Inquisitorial Procedure; see Ket. iii. 9). Two competent witnesses are indispensable.
- ("'We have not seen' is no proof" ['Eduy. ii. 2]). This principle was carried further in the Talmudic than it is in modern law, as the former was averse to the establishment of any fact by indirect evidence.
- ("Property [abides] in its status" [B. B. ix. 8-9; see Burden of Proof]). In the absence of evidence either way, property remains with the owner in possession, and his heirs.
- ("He who desires to take anything from his companion must furnish the proof" [B Ḳ. iii. 11; see Burden of Proof]); that is, the party seeking recovery of money or property must prove his case. The English rule is that the burden of proof rests upon the party having the affirmative in any issue; the Talmudic rule will often prove at variance with this practice.
- ("He who admits a part is bound to make oath" [Shebu. vi. 1-3]). One that is sued for a given sum or thing of value, and admits that he owes a smaller sum, or thing, thanthat claimed, or admits facts tending to such a conclusion, can not by his mere denial in regard to the balance put his adversary to proof; but he must, if the latter calls for it, confirm his denial by an oath.
- ("The mouth which bound [forbade] is the mouth that also loosened" ["permitted"; 'Eduy. iii. 6]). This maxim is given with this illustration:Where it is known of a woman only by her own account that she has been a captive, and she says she was not defiled, her statement is taken, and she may marry into the priesthood; but if the proof of her captivity rests upon witnesses, and she claims that she was not defiled, the court would say ("We do not live on what she says"; see also, for the rule, Ket. ii. 5, and, for its counterpart, Ket. i. 6-9).The general principle known as , with which the discussion of a branch of law in its details sometimes ends, is to be distinguished from the ordinary legal maxim. An example is found at the end of the treatise Shebu'ot, the last chapter of which states all the cases in which a depositary, by swearing to an untrue statement of fact, incurs guilt, and concludes with: "This is the general principle: 'Whoever swears in order to make it easier for himself, is guilty; to make it harder for himself, is not guilty.'" Legal maxims are to be distinguished from such sayings of worldly wisdom as: "He who has read the letter, let him carry out its purpose."