Presumption

The presumption is usually the assumption accepted in a field of knowledge about the truth or falsity of a fact, which is considered to be knowingly true in most cases. Such an assumption is a priori recognized true until facts are presented that clearly contradict him. The rationale for the presumption is usually the practical observations available and the theoretical concepts recognized in the field of knowledge. For example, the (purely statistical) fact that most people are not criminals can serve as a justification for the well-known presumption of innocence , therefore, in the absence of evidence of a person committing a crime, it is much more likely that he is not a criminal.

It is important to distinguish between presumption and axiom . The difference between these concepts is fundamental. The axiom is a theoretical proposition, chosen as the basis for a logical conclusion and within the theory accepted as an unconditional truth without evidence , while a presumption is a judgment derived from practice , which only sets the preferred order of investigation of various hypotheses. Any statement that contradicts the axiom within the theory is obviously false, while the contradiction of the presumption is quite possible, but requires justification, since it is considered much less likely.

Presumptions are widely used in jurisprudence . Among the most important legal presumptions:

• The presumption of innocence , applicable in criminal and criminal procedure law , as well as in constitutional law , as it is often enshrined in the constitution of the state;
• The presumption of guilt , applicable in civil law , and in some countries, in criminal law;
• The presumption of good faith applicable in civil and tax law ;
• Presumption of authorship as applied in copyright .
• The presumption of consent to the removal of organs and (or) tissues from a deceased person for their transplantation, applicable in medical law .
• The presumption of the spouse's consent to the disposition of the second spouse common property (his consent is assumed), family law .
• The presumption of environmental hazard of planned economic and other activities in environmental law .
• The presumption of death in the case of an unknown absence of a person beyond the statutory period. ^[1] .

In addition to this, there are other presumptions in legal practice, in particular the “ presumption of mental health ” ^[2] used in forensic psychiatry . For example, in article 3 of the Law of Ukraine “On Psychiatric Care” ^[3], it is defined as:

Each person is deemed not to have a mental disorder until the presence of such a disorder is established on the grounds and in the manner prescribed by this Law and other laws of Ukraine.

In the natural sciences, presumptions are often used implicitly, in the form of various methodological principles. One of the well-known general scientific presumptions is the so-called Occam’s Razor , which determines that among a number of hypotheses that explain the same phenomenon in different ways, all other things being equal, choose the one that attracts the smallest number of entities for explanation. This presumption, in turn, is based on the general methodological “principle of sufficient reason”, which requires that the introduction to the explanation of the new essence be reasonably justified. Examples of presumptions in the natural sciences:

• The principles of stratigraphy in geology and paleontology:
  • steno principle of layering, stating that if the geological layer A lies above layer B, it is most likely that layer B formed before layer A.
  • Huxley’s law, or the principle of the correspondence of flora and fauna, according to which geological layers containing the remains of the same species of animals and plants are likely to belong to the same time.

a combination of these principles allows us to establish a mutual arrangement of geological layers and synchronize the layers located in different places according to the time of formation, thus forming a global stratigraphic picture of the world.

• Determining the degree of kinship of living organisms by the similarity of structure. Here the presumption is used, according to which the inheritance by biological species of identical structural features from each other or from a common ancestor is more likely than the accidental occurrence of identical organs and systems in unrelated species.