As historians sort through conflicting evidence, they don’t settle into a conclusion too quickly. Instead, they think about every plausible interpretation, even when those interpretations conflict with each other. For example, if a historian was analyzing documents to try to decide whether the federal government knew that nuclear testing made people in southern Utah sick, the historian might consider several possible interpretations based on historical evidence:
- Maybe the federal government didn’t know that nuclear testing made people sick.
- Maybe the federal government knew that they were making people sick, and they lied to people about it.
- Maybe scientists knew that nuclear testing was making people sick, but they misinformed the federal government about it.
- Maybe some government officials knew about the dangers nuclear testing posed, but other government officials prevented their warnings from reaching the people.
- Maybe some government officials suspected that nuclear testing was making people sick, but they were not certain about it, so the people were not informed.
- Maybe government officials knew that nuclear testing made people sick but they thought that the good it accomplished outweighed the harm so they withheld information from people.
Each of these ideas represents a hypothesis, a proposed way to interpret the evidence. One of the remarkable things about historians is that they keep all these different hypotheses in mind, testing each of them with each new piece of evidence they find. Gradually, historians discard some of the possible interpretations as the evidence leads them to other hypotheses that are better supported by evidence. In the end, a historian reaches a conclusion that they can defend using all of the evidence. The ability to explore many competing interpretations is called hypothesis management.
Hypothesis Management Examples
The process of hypothesis management can be hard because of all the different but closely related ideas that the person has to remember at the same time. It might be helpful to write down different hypotheses in a table and test each one with each piece of evidence. For example, when testing the different theories about the downwinders, the historians might create a table like this, showing whether each piece of evidence supports an interpretation:
| Hypothesis | Document 1: Message | Document 2: Green Book | Document 3: House Report | Document 4: Butrico Story |
| The federal government didn’t know that nuclear testing made people sick. | Yes | No | No | No |
| The federal government knew they were making people sick, and they lied about it. | Maybe | Yes | Yes | Yes |
| Scientists knew they made people sick, but they misinformed the government. | No | No | No | No |
| Some government officials knew but others prevented their warnings. | Maybe | No | No | No |
| Some government officials suspected they made people sick, but they were not sure. | Maybe | Yes | No | No |
| Government officials knew they made people sick but they thought that the good it accomplished outweighed the harm. | Yes | Yes | Yes | Yes |
After completing the table, a person can see that the evidence supports the second and sixth possible interpretations. Some of the other possible conclusions would be hard to defend with the evidence in the archive. After thinking about it, the person might see that the second and sixth conclusions might both be correct—they aren’t contradictory.
Sometimes more than one interpretations might be partially correct. For example, four theories have been debated for years about the causes of the Mountain Meadows Massacre, some supported by historical evidence and others indefensible. In addition, the massacre may have been the result of a combination of these different hypotheses:
- Missouri Wildcats joined the peaceful pioneer group and tormented the Saints and Paiutes until the Saints attacked the entire company.
- Brigham Young coordinated the attack through George A. Smith.
- Arguments developed between the Saints and the pioneer group, with the Saints growing increasingly fearful about the pioneers’ support of an approaching US army.
- The emigrants were rich and were a tempting target for the impoverished Saints.
After weighing the evidence, the person could conclude that the massacre was a result of the third and fourth theories, and not the first or second theories. (There is no historical evidence supporting the Missouri Wildcat Theory, or the theory that Brigham Young ordered the attack, and some evidence shows that he did not order it). A pie chart might be used to show how the historian weighs the different causes that contributed to the tragedy.
A table or pie chart like these can help a historian weigh each possible interpretation against the evidence. They can prevent them from jumping to a conclusion too quickly, instead reaching the most defensible conclusion after looking at the evidence. With or without a table or chart, historians are skilled at managing a range of hypotheses as they weigh the evidence.