Reducing Terms
Sometimes a syllogism that is apparently fallacious because it is stated with more than three terms can be translated into an equivalent, valid three term syllogism. For example:
- Major premise: No humans are immortal.
- Minor premise: All Greeks are people.
- Conclusion: All Greeks are mortal.
This EAE-1 syllogism apparently has five terms: "humans", "people", "immortal", "mortal", and "Greeks". However it can be rewritten as a standard form AAA-1 syllogism by first substituting the synonymous term "humans" for "people" and then by reducing the complementary term "immortal" in the first premise using the immediate inference known as obversion (that is, "No humans are immortal." is equivalent to "All humans are mortal.").
Read more about this topic: Fallacy Of Four Terms
Famous quotes containing the words reducing and/or terms:
“Single acts of tyranny may be ascribed to the accidental opinion of a day; but a series of oppressions ... too plainly prove a deliberate, systematical plan of reducing us to slavery.”
—Thomas Jefferson (1743–1826)
“My father and I were always on the most distant terms when I was a boy—a sort of armed neutrality, so to speak. At irregular intervals this neutrality was broken, and suffering ensued; but I will be candid enough to say that the breaking and the suffering were always divided up with strict impartiality between us—which is to say, my father did the breaking, and I did the suffering.”
—Mark Twain [Samuel Langhorne Clemens] (1835–1910)