“Relations of Ideas” and “Matters of Fact”:

•Some ideas are logically connected: for example: “bachelor” to “unmarried,” “puppy” to “dog,” “4” to “2x2”: All bachelors are unmarried; all puppies are dogs; 2x2= (always) 4.
•In the above cases (and others like them) we have “necessary truths.” The above statements cannot be false. Such statements Hume calls “Relations of Ideas.”