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Encounter Engineering in Europe

What are Primary Sources

Primary sources are original materials (research, objects, documents) from the time period under study. They have not been interpreted, summarized, or analyzed. They were created during the period being studied and documents in some way what is being studied.

  • Interviews with experts (including the ones you may conduct for this class) 
  • Works of design, art, architecture, literature, music 
  • Eyewitness or site-visit accounts
  • Raw material or first-hand information
  • Artifacts (coins, clothing, furniture from the time under study)
  • Letters, diaries, photographs

Tips for Conducting Interviews

If you're conducting an interview, it is important to consider how you ask questions. Because you're relying on the answers the interviewee gives you, be sure your questions are written in a way to minimize bias. Review how to create good questions, especially those that minimize bias. 

Even with good questions, how you interpret your results will impact the credibility of your research. All researchers should strive to avoid these common mistakes:

Tips for Evaluating Primary Source Information

Assessing a person's credibility and bias can be difficult. Consider these criteria when determining whether a primary source is credible. 

  • N = Neutrality
  • E = Expertise
  • A = Ability to See
  • R = Reputation


Is your subject predisposed to support a particular point of view? A lack of neutrality of viewpoint can come if you have anything personally at stake. This is known as vested interested. It means you can gain advantage by saying or doing something. It is also possible for a subject to lack neutrality because of internal and external influences that inhibit them from thinking without bias. Someone who knows other people involved in a dispute, for example, may be liable to take a side, weakening their credibility.


Does your subject possess subject matter expertise? This can be demonstrated through degrees, years in the field, accolades, or job title. 

Ability to See

Is your subject in a position to know what they’re talking about? No matter how honest an interviewee, if they don’t have access to the evidence, then the value of their testimony is going to be limited. Consider whether the subject is providing a first-hand account. If they are, are there any conditions that may have obstructed their view or otherwise impaired their ability to relay the account accurately?


Does your subject's history or status suggest reliability? If you know that someone has told lies in the past, then you should be less trusting of them in future. You don't always know. Rely on indicators like if that person has been put in a position of authority and responsibility. This suggests that they have earned it, counting in their favor to some degree at least.

*Adapted from