# How many proofs does History require?

There's a well-known story about Andrey Kolmogorov. As a student his first choice of major was not Mathematics but History, and he wrote a serious paper on taxation of Russian serfs. He notices that the amount of taxes gathered from each village was always a whole number of roubles, but each individual household paid a fractional number. So Kolmogorov concluded that the taxes were levied by the landlord on the entire village as a unit, and then the villages would divide among themselves how much each household would pay. The landlord wouldn't bother himself with fractions, therefore each village's payment was always a whole number, but the individual households' contributions weren't.

When Kolmogorov showed his calculations the advisor was not convinced about the conclusions replied: "In History we need five different proofs for every assertion." After that Kolmogorov changed his major to Mathematics "because in Mathematics you only need one proof" and went on to develop modern Probability Theory and many other contributions to the subject.

Therefore the question: How many proofs are required for an assertion about a historic fact or trend would become generally accepted? What are the modern criteria for veracity of a historic fact?

• The story about Kolmogorov is great and surely answers your question in spirit: mathematics and history have antipodal logic. Knowledge in mathematics is acquired by streamlining, simplifying and conceptually trimming results. In history, knowledge is acquired by accumulating corroborating evidence for a claim. Consequently, the answer to your question is "the more, the better": one evidence in favor of a given claim is better than none, two better than one, etc... A historic fact or trend will be generally accepted if it has overwhelmingly more evidence in its favor than alternative accounts. Commented Oct 22, 2013 at 22:28
• Vote to keep open but clean up. As it is a decent historiography question. Unless we don't answer questions about the practice of history, in the same way that skeptics stack exchange doesn't answer questions about the practice of skeptism? Commented Oct 23, 2013 at 1:52
• We answer historiography questions. Commented Oct 23, 2013 at 3:36
• Nothing in history is ever proven; history is a dialogue with the past and the future.
– MCW
Commented Oct 23, 2013 at 12:41

IMO there is no number that can be specified as sufficient. Everything depends on the nature of the evidence and the sources presented:

In one case, we may have only one eyewitness account from a historical actor or witness, or one archeological artifact that is accepted as valid, and that may be enough to stand as historical proof.

In another case, we may have little or nothing in the way of good primary sources, and must accumulate many pieces of evidence, sometimes circumstantial, sometimes from sources of somewhat questionable reliability, until we build a case based on preponderance of evidence, as Samuel Russell has quite aptly explained.

Borrowing from other disciplines, we find three different thresholds of acceptable proof:

• Scientific or Mathematical Proof: An incontrovertible experiment or mathematical model.
• Criminal Law (USA): Beyond a reasonable doubt.
• Civil Law (USA): Preponderance of evidence - even if some reasonable doubt remains.

History most of the time is not nearly as clear cut as Science or Criminal Law. (The fact that this question has been asked is probably sufficient proof of that...) It is most akin to Civil Law in the threshold of proof required, since oftentimes no more is possible, particularly when dealing with events of the distant past. And so when dealing with History, any, (or certainly all) of the above will suffice, depending on the available sources and the manner in which they are presented.

Needless to say, the inviolability of any historical proof will depend on the strength of the evidence: The further we deviate from scientific proof and move towards preponderance of evidence, the weaker the "proof" may be.

• I don't want to poke holes in this - but there's a very big difference between a Scientific and Mathematical proof. Mathematical proof is absolute and for all time. Scientific proof is really an accumulation of evidence that supports a theorem. They are improved upon or overturned all the time. In some ways it's closer to 'beyond a reasonable doubt' than a Mathematical proof. Commented Dec 8, 2019 at 5:00

The answer lies in history being a discursive and inductive practice where our evidentiary materials are untrustworthy. A preponderance of the evidence, correctly interpreted, with a correct interpretation of what constitutes relevant evidence is required. This is obviously debatable. My invaluable peasant letters are your irrelevant ephemera.

Proofs can't be offered inductively; only unrefuted conjectures.

• "Get your dirty peasant letters away from me! Only pristine diaries from Lords of the Realm are allowed here!" - some historian in a tweed jacket. Commented Oct 23, 2013 at 5:42
• @LateralFractal Hilarious Commented Oct 23, 2013 at 11:23