1.2.  STATISTICS and PRECEDENT (or WHAT is the TRUE)

и     There is generally accepted in NAS, that one of obligatory qualities of a scientific research is reproducibility of its results in any place (not in only one laboratory), at any time and by any researcher. Accordingly, it is considered, that a researched phenomenon itself must all the more be reproducible.
   However, it is necessary to distinguish a research of an enough known and enough easily reproduced phenomenon, i.e. phenomenon existence/reality of which is doubtless (a), from a research of a phenomenon, which existence is doubtful (b), a research directed just to verification of its existence/reality.
   When parameters/characteristics of a phenomenon are ascertained (a), so its identical reproductions are really necessary for statistical estimations. However, if spontaneous displays of a phenomenon are observed extremely seldom (or even are unique – as the Tungus meteorite), and its artificial reproduction is extremely difficult or even inaccessible at all (b), a precedent must be accepted/admitted as the criterion of its reality reliability. So, even if the fireball would be observed even less often, than now (than it is observed actually), or even only once, the fact of its existence, the reliability of this fact, its "scientific character" would not become less.
   Moreover: unique phenomena are not a rarity. So, each record is unique (by definition: if it is not unique, it is any more a record), in particular – a sports one. Technologies of their reliability evaluation are worked through. A unique fact admits authentic if it is well fixed, and/or correctly firmed by papers, is confirmed legally – for example, by testimony, is approved by authoritative experts (as in art gymnastics and in other kinds of sports with elements of virtuosity; as in criminalistics, etc.).
   Always and in principle decisiveness can be declared to be doubtful, insufficient. Mathematics is a theoretical, ideological base of objectivism in a science. But even mathematicians admit: a proof is an argumentation convincing us so much, that we are ready to convince others with its help (V.A.Uspensky/В.А. Успенский, [ 130, p. 9]). It is methodologicalally important, that in principle (i.e. not casual and not temporary) not any true can be proved by objective methods, and any lie can be denied. You could not prove to me, that yesterday you had a headache even if you were, but on the other hand, and I could not prove, that you simulated, even if you hadn't any hurt.
   The right of a concept (not only scientific one) to exist is defined by impossibility to disprove it (at least today!) – by absence of its contradictions (both "external" – in relation to facts – and "internal"/logical ones), but not by its decisiveness/persuasiveness (also today!). Speaking in legal language, a concept should possess a presumption of reliability: until it is not disproved, it should be considered faultlessly authentic.
   В связи с природой уникальных явлений уместно упомянуть мнение Пьера Тейяра де Шарден (1881-1955): Природная аномалия – это всегда лишь преувеличение до ощутимости какого-либо свойства, всюду распространённого в неосязаемом виде. Какой-либо феномен, точно установленный хотя бы в одном месте, в силу фундаментального единства мира, необходимо имеет повсеместные корни и всеобщее значение [ 122, стр. 56].     и