ERROR. — From the Latin *errare*, to wander, stray, deviate, it is, in a broad sense, the departure from truth in thought and action; in the proper and restricted sense pertaining to knowledge, it is a judgment or affirmation that is objectively false. Accepting the definition of truth as “the conformity between thought and being,” error is therefore the mental affirmation or negation that is positively at variance with reality. From this original subjective sense, the objective sense has derived, whereby error sometimes serves as a synonym for a false proposition: thus one speaks, for instance, of errors contained in a doctrine or a system. As a mental affirmation positively at variance with reality, error, in the proper sense, must be essentially distinguished from purely negative error, which is used to indicate the mere inadequacy and incommensurability of human knowledge with reality.
The problem of error, on account of its connection with that of truth and the perplexing aporias to which it seems to give rise, has been, from antiquity, an object of interest and inquiry in philosophy. Protagoras, basing himself on the subjectivist principle that “man is the measure of all things” (Theaet., 152 A), denied the reality of error (Euthyd., 286 C). Plato, who considered the problem extensively and highlighted its difficulties, though affirming error as a judgment—inasmuch as it can unite two notions that ought to be distinguished—nevertheless did not arrive at an adequate determination of the causes of error, whose explanation was rendered more difficult by the theory of knowledge as the intuitive recollection of ideas. This indeterminacy regarding the origin and causes of erroneous assent persists in Aristotle, who tends to consider judgment more as an objective composition of concepts than as a synthetic-perceptive mental act. Nonetheless, Aristotle establishes the fundamental principle that truth and falsity are found only in the proposition, insofar as it is an affirmation that is either in conformity with or at variance with reality, and thus in the thought that expresses it (cf. Met., IV, 7, 101 b 25). Moreover, Aristotle emphasizes the illusions of the senses and alludes to the influence that will and temperament exert upon right judgment.
Voluntarism in the problem of error—a voluntarism of considerable complexity, insofar as it is connected with the question of original sin and its consequences—is accentuated in St. Augustine: error, as “that which is approved as true when it is false” (Contra Acad., I, 4, 11), is not “a fault of the intelligence; this, when illumined by the divine light, would not itself fall into error if the ill-disposed will and sensory impressions did not prevent the soul from attaining a pure vision of the truth” (cf. De Gen. ad litt., XII, 14, 29; De vera rel., 33, 62). St. Thomas, having posited a clear distinction between ignorance and error, adopts Augustine’s definition (De malo, q. 3, a. 7) and, following Aristotle, affirms that error is not found in simple intellectual perception (*simplex apprehensio*) but only in judgment (Sum. Theol., 1a, q. 17, a. 3), depending on the illusions of sensitive knowledge (De verit., q. 1, a. 11). Furthermore, the Angelic Doctor’s doctrine of assent as a formally intellectual act, together with the determining power attributed to the will when the intrinsic evidence of the object is lacking (Sum. Theol., 1a-2ae, q. 17, a. 6), leads to the conception of error as assent to a non-evident proposition, determined by the influence of the will upon the intellect.
In modern philosophy, the rigidly voluntaristic position of Descartes is well known: having affirmed assent as essentially a volitional act, error is entirely attributed to the will, which, being broader and more extensive than the intellect, in assenting oversteps the limits of intellectual perception (Meditations, IV, Italian trans. by A. Tilgher, I, Bari 1928, pp. 124–133; cf. Principles of Philosophy, I, 33). Bacon (v.) in the *Novum Organum* (I, 39 sqq.) offers a careful examination of the causes of error, reducing it to the innumerable prejudices and sociological (Italian) factors that disturb and impede objectivity in judgment. Spinoza conceives error in a purely negative sense, as a defect and limitation in knowledge (Eth., II, 35). In Kant, the problem becomes more acute on account of his particular subjectivist conception of truth, inherent to his system: having affirmed truth as the agreement of the cognitive act with the laws of thought, the author of criticism asserts that error, in itself, is not possible in the intellect or in sensation; it is found only in judgment, arising from the inverted influence of sensibility upon the intellect, whereby the subjective principles of judgment are mixed with the objective principles (cf. Critique of Pure Reason, Italian trans. by G. Gentile and C. Lombardo-Radice, I, Bari 1940, pp. 277–78).
In post-Kantian absolute idealism, with the denial of reality as a transcendent position to which thought must conform, one is logically led to the denial of error in its exaggerated sense as knowledge at variance with reality. In Gentile, error as a positive act of the spirit is impossible: the concept, inasmuch as it realizes itself in its eternal self-creative process, is necessarily true; yet, insofar as in this becoming process the concept has as its essential moment its own negation, it perpetually involves error as its non-being, eternally surpassed in the act. Thus error is not outside truth, but within truth (General Theory of the Spirit, 5th ed., Florence 1938, pp. 233–37).
The problem of error, accepting it in its traditional value—the specific position of idealism shares the fate of the general principles of the system—presents two main questions toward which historical inquiry has generally been directed: a) at what moments of knowledge does error occur; b) what are the causes by which it becomes possible and intelligible. As regards the locus of error, it is not properly found in forms of knowledge that are essentially passive, such as pure sensation or simple intellectual perception. The senses, in the proper sense, are not subject to error in their apprehension of their object: not in the sense that they always or necessarily refer to material reality as it is in itself, but in that the object is always given to them as it necessarily determines itself in the relationship between its objective conditions and the subjective structure of the sense; and this holds true both in normal and abnormal cases. The same applies, analogously, to simple intellectual apprehension, if one grants that it can be psychologically realized without a judgment, at least an implicit one. Error is possible only where there intervenes a spontaneous and active evaluation on the part of the knowing subject, that is, a judgment, whether initial and concrete (such is, in a certain sense, every perception and complex subjective construction of sensibility) or, principally, conceptual and pure (the judgment, in the proper sense, of the intellect).
The possibility of error, at this stage of human knowledge, can easily be understood if one bears in mind the nature of judgment and the various psychological factors it entails. For judgment, while formally an act of thought, often assumes the character of an integral psychological function in which the various psychic components constitutive of personality are engaged. In the selection and evaluation of objective data for the asserted synthesis, man brings to bear his temperament, his character, his habits, inclinations, tendencies, prejudices, passions, and all the particular conditions of mentality and culture in which his spirit has gradually been formed. If to this we add the various illusions arising from sensibility (external senses, imagination, memory), the limits of experience, and the essential inadequacy of human knowledge—which is the ultimate metaphysical root of the possibility of error—it is not difficult to see how judgment may frequently fail to correspond to the objective being of things. The aggregate of these factors contributes, on the one hand, to the presentation of the object under an inadequate and sometimes illusory aspect, and on the other, to the polarization of intellectual perception in a more or less partial and insufficient grasp of reality, obstructing the free and integral gaze of thought. And this is all the more frequent insofar as truth is more complex and interferes with the tendencies, exigencies, and commitments of the person and of life.
As regards the role of the will in error, the doctrine that makes the will directly responsible for the persistence of erroneous judgment, attributing to free will the power to determine assent beyond the limits permitted by the present cognitive reasons, does not seem acceptable. For even if such an influence of the will were possible, in this case the consciousness of the possibility of error would remain in the mind, and therefore, precisely for that reason, error as an absolutely negative stance of the spirit would not exist: one would not be in error when one is conscious that one’s affirmation may be mistaken. The direct influence of the will, if it exists in error, must, by the very nature of error, be unnoticed and unconscious. The will, however, as a fundamental factor of personality, retains in error a broad indirect influence, inasmuch as, through the general moral conditions it realizes in the human person and through the particular determinations it directs toward action, it predisposes the intellect, positively or negatively, toward the knowledge of truth. For this reason, error, like any other expression of human activity, is sometimes, but only in a causal and voluntary sense, imputable—and thus, to the extent of the morality and freedom of the remote conditions that have determined it, accountable.
In law — The divergences and contrasts encountered in philosophy regarding the concept and definition of error do not practically alter the terms in which the phenomenon must be considered from a juridical standpoint, where the problem—essentially directed toward the evaluation of the effects of error on human acts—is framed primarily in relation to the positive provisions of the various legal systems. Juridically, error is understood as a false judgment or representation, i.e., a judgment or representation that does not correspond to reality. Starting from this definition—which essentially reproduces the more concise one according to which error is the discrepancy between knowledge and reality—we can, setting aside any different philosophical conception, see on the concrete plane of law what influence error exerts on human actions, whether in the formation of a juridical act or in the perpetration of a crime. Error is in fact taken into consideration by law insofar as it determines the formation or declaration of a will that would not have been formed or declared without the false judgment or false representation of reality that constitutes the error.
Ignorance is often included within the juridical concept of error; but it seems more accurate to say that, although these are distinct concepts in themselves (inasmuch as error is a positive discrepancy between thought or knowledge and its object, while ignorance is merely a negative discrepancy, or in other words, one is inexact knowledge and the other is lack of knowledge), such a distinction is legally irrelevant, since with regard to the actions with which law alone is concerned, ignorance can influence the will only insofar as it is connected with error. As St Thomas explains well, “the act of the will presupposes an estimation or judgment concerning the object to which it tends; hence if there is ignorance here, there must also be error here” (*Sum. Theol.*, 3ª, q. 51, a. 1 ad 1).
Legal doctrine distinguishes error in juridical acts from various points of view. While the traditional distinction between error of law and error of fact has lost importance—inasmuch as the general principle of the irrelevance of error of law (in deference to the maxim *ignorantia iuris neminem excusat*) applies only in cases where the fact of deviant knowledge itself is considered—the distinction between proper and improper error remains fundamental. Proper error is that which is, in itself, the efficient cause of the defect in the act, inasmuch as, presupposing the existence of all the essential elements of the act, it vitiates consent and for this reason, under two conditions, renders the act itself voidable, thus giving error the right to challenge its validity. Improper error, on the other hand, is that which falls upon an essential element of the act: for example, upon the existence of the object (I sell a ship, unaware that it has meanwhile been wrecked), or upon its identity (I sell parcel A while the contractor intends to purchase parcel B), or upon the juridical nature of the act (I give a sum to C as a loan when he receives it as a gift). In the first case the sale does not exist, because the object is lacking; in the other two there is a total lack of consent, and hence the act does not exist. It is obvious that in all these hypotheses error is not the efficient cause of the non-existence of the act, but only the occasional cause.
Another more recent distinction, and only partially corresponding to the one just stated, is that between *errore mutuo ad accidentale*, or *errore visio* (*verum-multiè*), and *errore essentia dell’ostativo* (*errore-obstacle*). The former is that which affects the determining motives of the violation and vitiates the will in so far as it influences the motives thereof; the latter is that which determines a declaration different from the will, so that one declares to will what in fact one does not will. A distinction has also been made between *errore causam duos* (which affects the existence of the legally necessary premises of acts and is an occasional rather than an efficient cause of nullity) and *errore incidens* (the factual error that affects the direct object of the juridical act, i.e., the act considered in its constitutive elements); between *errore scusabile* and *inescusabile*, etc.; but obviously the practical utility of all these distinctions, not to mention their systematic value, is subordinate to the norms of the individual positive legal systems, to which, as we have said, the juridical study of the phenomenon must be referred.
In the legislative systems of the various States, *errore* is variously considered, both in the civil sphere, with regard to its influence on the various juridical acts, and in the penal sphere, and constitutes one of the most delicate subjects of discussion in jurisprudence. In the law of the Church, moreover, the discipline relating to *errore* presents particular interest on account of the importance which, even in relation to moral theology, the element of voluntarism assumes in canon law. (v. IGNORANZA).
For the evaluation of *errore* and ignorance (here practically equated) in relation to the activity of subjects in the juridical sphere, canon law first sets forth some fundamental norms. In these the legislator, after establishing that no one is presumed to be ignorant of the law (can. 16), lays down the following legal presumptions for the purpose of evaluating from an ethical standpoint the state of mind of the subject: ignorance or *errore* regarding the law or the penalty is not presumed, nor is it presumed regarding one’s own act or a notorious act of another; it is presumed, however, if it concerns a non-notorious act of another. In every case, contrary proof is admitted (can. 16 § 2).
Considering next, in particular, the disturbances of the will or intellect in so far as they affect juridical acts, the general rule holds good that *errore* which affects the substance of the act or falls upon a condition *sine qua non* invalidates the act itself juridically, except where particular provisions of law state otherwise. In contracts, however, *errore* may give rise to an action for rescission in accordance with the law (can. 16). In other words, acts performed through *errore* affecting the substance of the act or a condition essential thereto are void, that is to say, both *errore* regarding the transaction itself and *errore* regarding the motives, provided that the latter is such as to have determined the will. On the other hand, contracts entered into through *errore* whose rescindibility is established either by canon law (as in the case of *lesio enormis*: can. 1684 § 2) or by the territorial civil law (cf. can. 1529) are valid but voidable.
A special discipline governs the matter of *errore* in Marriage, which forms the subject of a group of norms (can. 1082–85) independent of the general principles set forth above. In the evaluation of *errore* in the process of formation and determination of the matrimonial will, the distinction between *errore* of law and *errore* of fact retains precise relevance.
The former only is a cause of invalidity of Marriage when it affects the essence of the contract-sacrament; it is required, namely, for the validity of this that the contracting parties be not ignorant (but after puberty such ignorance is not presumed) that Marriage is a permanent society between man and woman for the procreation of children. On the other hand, *errore* of law regarding the unity or indissolubility of Marriage, or its sacramental dignity, even if it gives rise to the contract, does not, according to canon law, constitute a defect of matrimonial consent. This principle is of intuitive importance for the validity of the Marriage of the unbaptized and non-Catholics. Likewise, *errore* of law constituted by the opinion of the nullity of Marriage (e.g., the erroneous belief in the existence of a diriment impediment) does not exclude matrimonial consent, nor does the knowledge of the actual nullity exclude II.
*Errore* of fact may affect the physical identity of the person or the qualities thereof. *Errore* regarding physical identity, where there is properly speaking a discrepancy between the manifestation of will and the real will (one might see here a typical instance of *errore ostativo*) and therefore an absolute lack of consent, renders the Marriage invalid. On the other hand, *errore* regarding the qualities of the person generally does not affect the validity of the Marriage even if it gave rise to the contract, except in the following cases: a) *errore* regarding qualities which redound to an *errore* of person, that is to say, where the quality serves to individuate the person who was taken into consideration exclusively by the other contracting party (but this is a concept difficult to define precisely and much discussed); b) *errore* regarding the condition of servitude, i.e., the state of slavery (*servitus proprie dicta*) of the other contracting party. It is to be noted, however, that while *errore* regarding other personal qualities (health, virginity, nobility, economic status, etc.) does not of itself affect the validity of consent, the existence or non-existence of the same, like any other past or present circumstance, may be an element determining the validity or invalidity of the Marriage when consent has been made dependent thereon as a condition (can. 1092, n. 4).
From the penal standpoint, *errore* (here also equated with ignorance; can. 2202 § 3) may be taken into consideration for the purpose of evaluating imputability and the application of penalties. Canon law, breaking sharply here with the state penal codes which have adopted the maxim *ignorantia legis non excusat*, considers among the causes which exclude imputability—inasmuch as they remove the very basis of penal imputability, because they suppress the subjective (voluntary) element—the ignorance of the law, provided it is inculpable; otherwise imputability is diminished in proportion to the culpability of the ignorance. Ignorance of the penalty alone does not exclude imputability but diminishes II. The same rules apply to *errore* (can. 222). The causes which totally exclude imputability, or exclude its gravity—and hence also *errore*—equally excuse from penalty (can. 2218 § 2). As regards *penae latae sententiae* (v. PENA), the law considers, besides invincible ignorance, which involves no imputability of the agent and therefore excludes every penalty, three other hypotheses of ignorance: affected ignorance, i.e., knowingly willed, which never excuses from penalty; vincible ignorance, crass or stupid, which excuses from penalty only when it is attached to a law which expressly requires full and mature knowledge and deliberation; and vincible but not crass or stupid ignorance, and therefore implying a lesser degree of imputability (*simpliciter vincibilis*), which excuses also (in addition to penalties attached to laws as above) from medicinal penalties attached by other laws, but not from vindictive penalties *latae sententiae* (can. 2229 §§ 1, 3, n. 10).
As regards *errore* against the Faith, V. ERESIA; for the common theory of *errore*, V. GIURISDIZIONE. For *errore* in moral theology, V. IGNORANZA.