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The balance scales seen in depictions of Lady Justice can be seen as representing the weighing of evidence in a legal proceeding. Dublin Castle Gates of Fortitude and Justice 05.JPG
The balance scales seen in depictions of Lady Justice can be seen as representing the weighing of evidence in a legal proceeding.

Evidence, broadly construed, is anything presented in support of an assertion, [1] because evident things are undoubted. There are two kind of evidence: intellectual evidence (the obvious, the evident) and empirical evidence (proofs).


The mentioned support may be strong or weak. The strongest type of evidence is that which provides direct proof of the truth of an assertion. At the other extreme is evidence that is merely consistent with an assertion but does not rule out other, contradictory assertions, as in circumstantial evidence.

In law, rules of evidence govern the types of evidence that are admissible in a legal proceeding. Types of legal evidence include testimony, documentary evidence, and physical evidence. [2] The parts of a legal case which are not in controversy are known, in general, as the "facts of the case." Beyond any facts that are undisputed, a judge or jury is usually tasked with being a trier of fact for the other issues of a case. Evidence and rules are used to decide questions of fact that are disputed, some of which may be determined by the legal burden of proof relevant to the case. Evidence in certain cases (e.g. capital crimes) must be more compelling than in other situations (e.g. minor civil disputes), which drastically affects the quality and quantity of evidence necessary to decide a case.

Scientific evidence consists of observations and experimental results that serve to support, refute, or modify a scientific hypothesis or theory, when collected and interpreted in accordance with the scientific method.

In philosophy, the study of evidence is closely tied to epistemology, which considers the nature of knowledge and how it can be acquired.

Intellectual evidence (the evident)

The first thing discovered in history is that evidence is related to the senses. A footprint has stayed in the language: the word anchors its origin in the Latin term evidentia, which comes from videre, vision. In this sense, evidence is what falls under our eyes. Something similar happened in ancient philosophy with Epicurus. He considered all knowledge to be based in sensory perception: if something is perceived by the senses, it is evident, it is always true (cf. Letter to Diogenes Laertius, X, 52).

Aristotle went beyond that concept of evidence as simple passive perception of the senses. He observed that, although all superior animals could have sensory experiences of things, only human beings had to conceptualize them and penetrate more and more into their reality (cf. Metaphysics, 449, b; About the Memory, 452, a; Physics I, c. 1). This certain understanding that the intellect obtains things when it sees them, it makes it in an innate and necessary way (it is not something acquired, as can be the habit of science, of which he speaks in Ethics IV). For Aristotle the evidence it not merely passive perception of reality, but a gradual process of discoveries, a knowledge that "determines and divides" better and better the "undetermined and undefined": it begins with what is most evident for us, in order to end with what is truer and more evident in nature.

Aquinas would later deepen the distinction of evidence quad nos and quad se already suggested by Aristotle (cf. Summa Th. I, q. 2, sol.). Neither of the two understood evidence in purely logical or formal terms, like many schools of thought tend to understand today. His theory of knowledge proves to be much richer. In philosophical realism, the senses (sight, sound, etc.) provide correct data of what reality is; they do not lie to us, unless they are atrophied. When the sensitive species (or the Aristotelian phantom) formed by the inferior powers is captured by intelligence, it immediately knows and abstracts data from reality; the intelligence with its light, through "study", "determination" and "division" will end up forming concepts, judgements and reasoning. That first immediate acquisition of reality, devoid of structured reasoning, is the first evidence captured by the intellect. Then the intellect is aware of other obvious truths (such as 2+2=4 or that "the total is greater than or equal to the part") when it compares and relates the previously assimilated knowledge.

Scholastic tradition considered that there existed some "primary principles of practical reason", known as immediately and clearly, that could never be broken or repealed. These moral principles would be the most nuclear of natural law. But in addition to those, there would be another part of natural law (formed by deductions or specifications of those principles) that could vary with time and with changing circumstances (cf. Summa Th. I-II, q. a. 5, sol.). In this way, the natural law would consist of some small immutable principles and by enormous variable content.

Finnis, Grisez and Boyle [3] point out that what is self-evident cannot be verified by experience, nor derived from any previous knowledge, nor inferred from any basic truth through a middle ground. Immediately they point out that the first principles are evident per se nota, known only through the knowledge of the meanings of the terms, and clarify that "This does not mean that they are mere linguistic clarifications, nor that they are intuitions-insights unrelated to data. Rather, it means that these truths are known (nota) without any middle term (per se), by understanding what is signified by their terms." Then when speaking specifically about the practical principles, they point out that they are not intuitions without contents, but their data come from the object to which natural human dispositions tend, that motivate human behavior and guide actions (p. 108). Those goods to which humans primarily tend, which cannot be "reduced" to another good (it is to say, that they are not means to an end), they are considered "evident": "as the basic good are reasons with no further reasons" (p. 110).

George Orwell (2009) considered that one of the principal duties of today's world is to recover what is obvious. Actually, when the manipulation of language for political ends grows strongly, when "war is peace", "freedom is slavery", "ignorance is strength", it is important to rediscover the basic principles of the reason. Riofrio has designed a method to validate which ideas, principles or reasons can be considered "evident", testing in that ideas all the ten characteristics of the evident things. [4]

Empirical evidence (in science)

In scientific research evidence is accumulated through observations of phenomena that occur in the natural world, or which are created as experiments in a laboratory or other controlled conditions. Scientific evidence usually goes towards supporting or rejecting a hypothesis.

The burden of proof is on the person making a contentious claim. Within science, this translates to the burden resting on presenters of a paper, in which the presenters argue for their specific findings. This paper is placed before a panel of judges where the presenter must defend the thesis against all challenges.

When evidence is contradictory to predicted expectations, the evidence and the ways of making it are often closely scrutinized (see experimenter's regress) and only at the end of this process is the hypothesis rejected: this can be referred to as 'refutation of the hypothesis'. The rules for evidence used by science are collected systematically in an attempt to avoid the bias inherent to anecdotal evidence.


An FBI Evidence Response Team gathering evidence by dusting an area for fingerprints FBI Evidence Response Team.jpg
An FBI Evidence Response Team gathering evidence by dusting an area for fingerprints

In law, the production and presentation of evidence depends first on establishing on whom the burden of proof lies. Admissible evidence is that which a court receives and considers for the purposes of deciding a particular case. Two primary burden-of-proof considerations exist in law. The first is on whom the burden rests. In many, especially Western, courts, the burden of proof is placed on the prosecution in criminal cases and the plaintiff in civil cases. The second consideration is the degree of certitude proof must reach, depending on both the quantity and quality of evidence. These degrees are different for criminal and civil cases, the former requiring evidence beyond a reasonable doubt, the latter considering only which side has the preponderance of evidence, or whether the proposition is more likely true or false. The decision maker, often a jury, but sometimes a judge, decides whether the burden of proof has been fulfilled.

After deciding who will carry the burden of proof, evidence is first gathered and then presented before the court:


In criminal investigation, rather than attempting to prove an abstract or hypothetical point, the evidence gatherers attempt to determine who is responsible for a criminal act. The focus of criminal evidence is to connect physical evidence and reports of witnesses to a specific person. [5]


The path that physical evidence takes from the scene of a crime or the arrest of a suspect to the courtroom is called the chain of custody. In a criminal case, this path must be clearly documented or attested to by those who handled the evidence. If the chain of evidence is broken, a defendant may be able to persuade the judge to declare the evidence inadmissible.

Presenting evidence before the court differs from the gathering of evidence in important ways. Gathering evidence may take many forms; presenting evidence that tend to prove or disprove the point at issue is strictly governed by rules. Failure to follow these rules leads to any number of consequences. In law, certain policies allow (or require) evidence to be excluded from consideration based either on indicia relating to reliability, or broader social concerns. Testimony (which tells) and exhibits (which show) are the two main categories of evidence presented at a trial or hearing. In the United States, evidence in federal court is admitted or excluded under the Federal Rules of Evidence. [6]

Burden of proof

The burden of proof is the obligation of a party in an argument or dispute to provide sufficient evidence to shift the other party's or a third party's belief from their initial position. The burden of proof must be fulfilled by both establishing confirming evidence and negating oppositional evidence. Conclusions drawn from evidence may be subject to criticism based on a perceived failure to fulfill the burden of proof.

Two principal considerations are:

  1. On whom does the burden of proof rest?
  2. To what degree of certitude must the assertion be supported?

The latter question depends on the nature of the point under contention and determines the quantity and quality of evidence required to meet the burden of proof.

In a criminal trial in the United States, for example, the prosecution carries the burden of proof since the defendant is presumed innocent until proven guilty beyond a reasonable doubt. Similarly, in most civil procedures, the plaintiff carries the burden of proof and must convince a judge or jury that the preponderance of the evidence is on their side. Other legal standards of proof include "reasonable suspicion", "probable cause" (as for arrest), " prima facie evidence", "credible evidence", "substantial evidence", and "clear and convincing evidence".

In a philosophical debate, there is an implicit burden of proof on the party asserting a claim, since the default position is generally one of neutrality or unbelief. Each party in a debate will therefore carry the burden of proof for any assertion they make in the argument, although some assertions may be granted by the other party without further evidence. If the debate is set up as a resolution to be supported by one side and refuted by another, the overall burden of proof is on the side supporting the resolution.


See also

Related Research Articles

Empiricism Theory that states that knowledge comes only or primarily from sensory experience

In philosophy, empiricism is a theory that states that knowledge comes only or primarily from sensory experience. It is one of several views of epistemology, along with rationalism and skepticism. Empiricism emphasizes the role of empirical evidence in the formation of ideas, rather than innate ideas or traditions. However, empiricists may argue that traditions arise due to relations of previous sense experiences.

Scientific method Interplay between observation, experiment and theory in science

The scientific method is an empirical method of acquiring knowledge that has characterized the development of science since at least the 17th century. It involves careful observation, applying rigorous skepticism about what is observed, given that cognitive assumptions can distort how one interprets the observation. It involves formulating hypotheses, via induction, based on such observations; experimental and measurement-based testing of deductions drawn from the hypotheses; and refinement of the hypotheses based on the experimental findings. These are principles of the scientific method, as distinguished from a definitive series of steps applicable to all scientific enterprises.

Thomas Reid Scottish philosopher

Thomas Reid was a religiously trained Scottish philosopher. He was the founder of the Scottish School of Common Sense and played an integral role in the Scottish Enlightenment. In 1783 he was a joint founder of the Royal Society of Edinburgh. A contemporary of David Hume, Reid was also "Hume's earliest and fiercest critic".

A theory is a contemplative and rational type of abstract or generalizing thinking about a phenomenon, or the results of such thinking. The process of contemplative and rational thinking often is associated with such processes like observational study, research. Theories may either be scientific or other than scientific. Depending on the context, the results might, for example, include generalized explanations of how nature works. The word has its roots in ancient Greek, but in modern use it has taken on several related meanings.

Begging the question Type of fallacy, where a proposition is assumed as a premise, which itself needs a proof and directly entails the conclusion

In classical rhetoric and logic, begging the question or assuming the conclusion is an informal fallacy that occurs when an argument's premises assume the truth of the conclusion, instead of supporting it.

A fact is an occurrence in the real world. The usual test for a statement of fact is verifiability—that is whether it can be demonstrated to correspond to experience. Standard reference works are often used to check facts. Scientific facts are verified by repeatable careful observation or measurement by experiments or other means.

Burden of proof is a legal duty that encompasses two connected but separate ideas that apply for establishing the truth of facts in a trial before tribunals in the United States: the "burden of production" and the "burden of persuasion." In a legal dispute, one party is initially presumed to be correct, while the other side bears the burden of producing evidence persuasive enough to establish the truth of facts needed to satisfy all the required legal elements of legal dispute. There are varying types of burden of persuasion commonly referred to as standards of proof, and depending on the type of case, the standard of proof will be higher or lower. Burdens of persuasion and production may be of different standards for each party, in different phases of litigation. The burden of production is a minimal burden to produce at least enough evidence for the trier of fact to consider a disputed claim. After litigants have met the burden of production, they have the burden of persuasion: that enough evidence has been presented to persuade the trier of fact that their side is correct. There are different standards of persuasiveness ranging from a preponderance of the evidence, where there is just enough evidence to tip the balance, to proof beyond a reasonable doubt, as in United States criminal courts.

Philosophical skepticism is a family of philosophical views that questions the possibility of knowledge or certainty. Philosophical skeptics are often classified into two general categories: Those who deny all possibility of knowledge, and those who advocate for the suspension of judgement due to the inadequacy of evidence. This is modeled after the differences between the Academic skeptics and the Pyrrhonian skeptics in ancient Greek philosophy.

An affirmative defense to a civil lawsuit or criminal charge is a fact or set of facts other than those alleged by the plaintiff or prosecutor which, if proven by the defendant, defeats or mitigates the legal consequences of the defendant's otherwise unlawful conduct. In civil lawsuits, affirmative defenses include the statute of limitations, the statute of frauds, waiver, and other affirmative defenses such as, in the United States, those listed in Rule 8 (c) of the Federal Rules of Civil Procedure. In criminal prosecutions, examples of affirmative defenses are self defense, insanity, and the statute of limitations.

Empirical evidence is the information received by means of the senses, particularly by observation and documentation of patterns and behavior through experimentation. The term comes from the Greek word for experience, ἐμπειρία (empeiría).

The presumption of innocence is the legal principle that one is considered "innocent until proven guilty".

<i>Meditations on First Philosophy</i> Philosophy book by Descartes

Meditations on First Philosophy, in which the existence of God and the immortality of the soul are demonstrated is a philosophical treatise by René Descartes first published in Latin in 1641. The French translation was published in 1647 as Méditations Métaphysiques. The title may contain a misreading by the printer, mistaking animae immortalitas for animae immaterialitas, as suspected by A. Baillet.

Inductive reasoning is a method of reasoning in which the premises are viewed as supplying some evidence, but not full assurance, of the truth of the conclusion. It is also described as a method where one's experiences and observations, including what are learned from others, are synthesized to come up with a general truth. Many dictionaries define inductive reasoning as the derivation of general principles from specific observations, although there are many inductive arguments that do not have that form.

The laws of thought are fundamental axiomatic rules upon which rational discourse itself is often considered to be based. The formulation and clarification of such rules have a long tradition in the history of philosophy and logic. Generally they are taken as laws that guide and underlie everyone's thinking, thoughts, expressions, discussions, etc. However, such classical ideas are often questioned or rejected in more recent developments, such as intuitionistic logic, dialetheism and fuzzy logic.

Pseudoskepticism is a philosophical or scientific position that appears to be that of skepticism or scientific skepticism but in reality fails to be.

The law of evidence, also known as the rules of evidence, encompasses the rules and legal principles that govern the proof of facts in a legal proceeding. These rules determine what evidence must or must not be considered by the trier of fact in reaching its decision. The trier of fact is a judge in bench trials, or the jury in any cases involving a jury. The law of evidence is also concerned with the quantum (amount), quality, and type of proof needed to prevail in litigation. The rules vary depending upon whether the venue is a criminal court, civil court, or family court, and they vary by jurisdiction.

The Cartesian circle is a potential mistake in reasoning attributed to René Descartes.

"The Will to Believe" is a lecture by William James, first published in 1896, which defends, in certain cases, the adoption of a belief without prior evidence of its truth. In particular, James is concerned in this lecture about defending the rationality of religious faith even lacking sufficient evidence of religious truth. James states in his introduction: "I have brought with me tonight ... an essay in justification of faith, a defense of our right to adopt a believing attitude in religious matters, in spite of the fact that our merely logical intellect may not have been coerced. 'The Will to Believe,' accordingly, is the title of my paper."

The burden of proof is the obligation on a party in a dispute to provide sufficient warrant for their position.

Evidential burden or "production burden" is the obligation to produce evidence to properly raise an issue at trial. Failure to satisfy the evidential burden means that an issue cannot be raised at a court of law.


  1. Davis Oldham: 'Evidence' (English 101 & 102) at Shoreline Community College, shoreline.edu Accessed 18 June 2017
  2. American College of Forensic Examiners Institute. (2016). The Certified Criminal Investigator Body of Knowledge. Boca Raton, Florida: CRC Press. pp. 112–113. ISBN   978-1-4987-5206-0
  3. Grisez, G; Boyle, J; Finnis, J (1987). "Practical Principles, Moral Truth, and Ultimate Ends". The American Journal of Jurisprudence The American Journal of Jurisprudence. 32 (1): 99–151. ISSN   0065-8995. OCLC   4916618288.
  4. Riofrio, Juan Carlos (2019). "Evidence and its Proof: Designing a Test of Evidence". Forum Prawnicze (3(53)). doi:10.32082/fp.v3i53.219. ISSN   2081-688X.
  5. Roscoe, H.; Granger, T.C. (1840). A Digest of the Law of Evidence in Criminal Cases. p.  9 . Retrieved 11 March 2020.
  6. "Federal Rules of Evidence 2008". Federal Evidence Review. Archived from the original on 19 August 2010. Retrieved 18 July 2008.