1 : the process of exact thinking : reasoning
2 : a reasoned train of thought
"There was very little ratiocination involved; very little intellect came into play." - From Brad Meltzer's 2011 thriller The Inner Circle
"The detective uses a method-whether it is science, some other ratiocination or even intuition-to put things back to normal." - From an article by Eric Felton on WallStreetJournal.com, September 20, 2012
Did You Know?
Edgar Allan Poe is said to have called the 1841 story The Murders in the Rue Morgue his first "tale of ratiocination." Many today agree with his assessment and consider that Poe classic to be the world's first detective story. Poe didn't actually use "ratiocination" in Rue Morgue, but the term does appear three times in its 1842 sequel, The Mystery of Marie Roget. In Marie Roget, the author proved his reasoning ability ("ratiocination" traces to "ratio," Latin for "reason" or "computation"). The second tale is based on an actual murder, and as the case unfolded after the publication of Poe's work, it became clear that his fictional detective had done an amazing job of reasoning through the crime.
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Word Family Quiz
What relative of "ratiocination" can mean "a food allowance for one day"? The answer is ...