Genealogical Fallacies Project: Pitfalls in Research Methods

Kory L. Meyerink, MLS, AG®, FUGA

Welcome to the Genealogical Fallacies Project, an effort to identify, catalog, define, and overcome the dozens of fallacies occurring in modern family history research.

Family historians, or genealogists, especially those newly engaged in the search for ancestors, sometimes fall prey to a fallacy, or as Webster puts it, An often plausible argument using false or invalid inference (Webster’s Ninth New Collegiate Dictionary).

Genealogical research can be complex, due to the wide variety of records, time periods, and circumstances we must deal with. While any researcher may make mistakes, it is a major concern when such errors are the result of false or simplistic understandings of genealogical methods and sources. However, such errors can be overcome. A growing list of such fallacies can help everyone become both better and more efficient researchers. An exploration of typical fallacies can explain how and why genealogists make wrong connections, and can lead to overcoming such errors.

Inspired by Historian's Fallacies, the groundbreaking book by David Hackett Fischer (Harper, 1970), this project echoes his subtitle, encouraging us to move toward a logic of [genealogical] thought by carefully understanding the unfounded presumptions we bring to our genealogical research. As noted genealogist Val Greenwood wrote, "Genealogy will reach its proper place of respectability among the sciences only as we, its devotees, adopt sound scientific principles in our research. We must learn to consider all relevant evidence before we reach our conclusions.No scientist would do less." (Researcher’s Guide, 1990, p. 8)

The word fallacy has different meanings to different people. In addition to the above definition, other meanings include:

  • A false or erroneous idea, (generally misleading or illusory) (Webster’s International)
  • Plausible but invalid reasoning (WordPerfect Thesaurus).

This project uses the broadest meaning of a false or erroneous idea, and therefore a misleading concept.

Genealogists (as a whole) are likely not very different from other researchers; everyone may sometimes make invalid arguments or promote a false idea. The problem is that such false ideas can easily lead to invalid conclusions of relationships, or a premature end to family research.

Is every instance of a condition cited in these fallacies always wrong? No, of course not. There are persons of noble descent; sometimes the records were destroyed, some family traditions are correct. However, accepting such assertions without examination is poor research methodology. By alerting us all to these possible pitfalls, ProGenealogists's Genealogical Fallacies Project seeks to make all family historians more cautious and accurate in their research conclusions.

Due to the great variety of genealogical records and ancestral circumstances, any one of us might fall prey to one or more of these fallacies from time to time. Humility is a useful trait for even the best researchers. This project offers a way to explore the different kinds of false or erroneous ideas or plausible but invalid reasoning (alternate definitions of fallacies) which occur too often in our chosen field of family history. It will also offer alternative approaches to the problems presented, thus helping to provide the means to overcome such fallacies.

Many fallacies are already tentatively identified on this website. Reader feedback, nominations, examples and essays are welcome!

Selected Genealogical Fallacies Arranged by Class

Type of Fallacy -

Definition and/or Example

Fallacies of Misconception - Misunderstandings about Genealogical Research
Easiness - Family history is easy and takes little training
Completion - Finding all ancestors, or believing: "my genealogy is all done "
Shallowness - Genealogy is just charts
Ancestors as islands - An ancestor is not affected by the events surrounding them.
 Fallacies of Tradition - Unquestioned acceptance of family traditions
Noble descent - Family is of noble or royal descent
Native American - An ancestor was a Native American; possible benefits are due
Elevated importance - Ancestor/relative was of greater importance in society really was
Fallacies of Sources - Misunderstanding sources, including their origin, content, and availability
Missing records - Can't solve a problem due to lost or destroyed sources
Abstracts - All the important information is in the abstract
Computer Databases - Databases are complete and/or comprehensive
Over-reliance - Using one or two record sources too much, limited use of other sources.
Fallacies of Credibility - Improper or unwarranted acceptance of information
Honest informants - Grandma would not lie, therefore her statements are true
Ready acceptance - Accepting a conclusion because of the proponent; Aunt Mabel knew the situation
Family tradition - Giving it too much weight
Repetition - Same statement repeated by author many times is more convincing
Fallacies of Interpretation - Misunderstanding the information found in sources
Misread documents - Misreading and thereby misjudging a document
 Current culture - Applying modern culture/standards to historical research
Single Interpretation - Seeing only one way to view the evidence
Archaic definitions - Not understanding former definitions of words whose meaning has altered (i.e.: in-law can mean step-)
Fallacies of Hypothesis - Erroneous theories that researchers assume and/or try to provein their research
Best/only hypothesis - Rigid determinism to prove a first hypothesis
Limited candidates - Ancestor is either this man or that man
Proximity in place - Person must be related to others nearby with same surname origin, ethnicity, etc.
Fallacies of Generalization - Assuming Averages must Apply in a Specific Ancestral Situation
Application of averages - Inappropriate dependence on average situations (age at marriage)
Deductive Reasoning - Assuming specifics from general tendencies.
Inductive Reasoning - Assuming a generalized pattern from specific instances
 Fallacies of Research -  Poor Approaches to Research Problems
Ignored descendants - Not tracing family members who did not have descendants
Ignored associates - Not identifying other persons mentioned in a record about the subject
False end-of-line - Assuming a genealogy which shows no children means the family had no children
Fallacies of Chronology - Inadequate Consideration of Chronological Elements
Telescoping generations - Especially in databases and mediaeval lines
Too early settlement - Placing persons in a local before it was settled
Poor chronology - Not paying attention to the ages at events
Fallacies of Proof - False understandings of the nature of evidence and proof
Limited Sources - Seeking to prove events from the most common sources andignoring other sources for that event.
Evidence as proof - Mistaking evidence for proof.
Insufficient proof - Not compiling sufficient evidence to substantiate the theory.
Unproven conclusion - Deciding a relationship before sufficient facts support it.
 Quantity of proof - Greater number of similar statements equals stronger proof
 Intuition - A fact or relationship feels good, must be true
Fallacies of Documentation - Mistaken notions about what constitutes adequate documentation
Not listing sources - They are self-evident
Broad statements of proof - I used "everything"
Unnecessary proof - The information is self-evident, or the reader candetermine where I got the information.
Fallacies of Imprecision - Ambiguous attitudes and presentations of findings
Imprecise writing - Unclear or ambiguous discussion of findings
Inconclusive conclusions - Likely, surely, of course, certainly, usually, probably
Diminishing cautions - Use of possibly likely, probably, certainly

The scholar [must] be constantly alert to the need of testing and revising his images, beliefs, and conceptions of the area of life he is studying. He should cultivate assiduously a readiness to view his area of study in new ways. [Herbert Blumer, Symbolic Interactionism; Perspective and Method, p. 41.]


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