The Genetic of Origin Fallacy is the false idea that original definitions constrain current definitions. This denies the evolution of an idea, constraining it to it’s infant definitions. Ideas grow and evolve, so referring back to the source of the idea to undermine the latest research and ideas is a false use of the concept.
This is a frequent logical fallacy that I have spotted historians attempt to use when looking at the psychology of historical figures. In history, the older a source is, the more accurate it is. That’s great when trying to work out what happened many years ago, however that is not good when trying to analyse something based on the first conception of that idea. For example, attempting to understand the psychology of why people have done what they did should use the most up to date concepts of psychology rather than the original Freudian Psychoanalysis. Going back to the source of modern ideas does not give you a more accurate concept, it gives you a more ‘primitive’ concept that is now outdated and has many corrections.
Another attempt to use the Genetic or Origin Fallacy is to suggest that the modern conception of evolution is faulty because Charles Darwin made some errors in his original theories. Of course there were some errors which have since been discovered and corrected for. If Darwin had conceived of the entirety of the concept and written an immutable copy of the concept in his book, “The Origin of Species”, then the scientists that have been researching and refining the concept over the last hundred or so years have wasted their time. Just go back and read the book. This isn’t the case – so much has been learned from the launching pad of “The Origin of Species”. The same is true in all schools of scientific knowledge.
Words also evolve. If you look at the original etymology of words, you will find that many words no longer mean what they use to. Decimate is one of my favourites. Etymologically speaking, decimate means “to kill 1 in 10”. So when your forces are decimated, you lost 1 out of every 10 soldiers. Nowadays the word is generally used to mean “massacred”, which means “deliberate and brutal killing”, which implies complete or near complete devastation. When people use “decimate” in a modern context, one must consider that they may mean “massacre” rather than “1 in 10”. To hold a modern use of the word “decimate” in error because it use to mean something else is an error in constraining the modern word for the original word, or it’s genetic origin.