philosophy Philosophy (from , ) is the systematized study of general and fundamental questions, such as those about existence, reason, knowledge, values, mind, and language. Such questions are often posed as problems to be studied or resolved. ...

, a relation is a type of fact that is true or false of two things. For instance, "being taller than" is a relation that is true of "

Shaquille O'Neal Shaquille Rashaun O'Neal ( ; born March 6, 1972), known commonly as "Shaq" ( ), is an American former professional basketball player who is a sports analyst on the television program '' Inside the NBA''. O'Neal is regarded as one of the greate ...

and

Ross Perot Henry Ross Perot (; June 27, 1930 – July 9, 2019) was an American business magnate, billionaire, politician and philanthropist. He was the founder and chief executive officer of Electronic Data Systems and Perot Systems. He ran an indepe ...

" and false of "the Empire State building and Mt. Everest." Substances or things have properties ("this spot is red"). Relations on the other hand obtain between two substances ("this spot is bigger than that spot") or two properties ("this red is a darker shade than that red"). There are two major kinds of relations: ontological and epistemological. Ontological relations are entities like "father", which is a person considered in his relation ''to'' a child. Epistemological relations are often logical connections that obtain between two concepts or ideas, like "entailment." The fact that all men are mortal and that Socrates is a man entails that Socrates is mortal—the relation between Socrates' mortality and the mortality of all men is an entailment relation.

Relations in modern philosophy

Relation of Ideas, in the Humean sense, is the type of knowledge that can be characterized as arising out of pure conceptual thought and logical operations (in contrast to a Matter of Fact). For instance, in mathematics: 8 x 10 = 80. Or in Logic: All islands are surrounded by water (by definition). In

Kantian Kantianism is the philosophy of Immanuel Kant, a German philosopher born in Königsberg, Prussia (now Kaliningrad, Russia). The term ''Kantianism'' or ''Kantian'' is sometimes also used to describe contemporary positions in philosophy of mind, ...

philosophy, a relation is equivalent to the

analytic Generally speaking, analytic (from el, ἀναλυτικός, ''analytikos'') refers to the "having the ability to analyze" or "division into elements or principles". Analytic or analytical can also have the following meanings: Chemistry * ...

a priori ("from the earlier") and ("from the later") are Latin phrases used in philosophy to distinguish types of knowledge, justification, or argument by their reliance on empirical evidence or experience. knowledge is independent from current ex ...

''. Unlike Hume, Kant denied, in the introduction to his "Critique of Pure Reason", that mathematical truths were analytic.Immanuel Kant, ''Critique of Pure Reason'', Introduction Rather, 'a bachelor is unmarried' is true by relation of the definitions of the concepts of 'bachelor' and 'unmarried.' In

Leibniz Gottfried Wilhelm (von) Leibniz . ( – 14 November 1716) was a German polymath active as a mathematician, philosopher, scientist and diplomat. He is one of the most prominent figures in both the history of philosophy and the history of ma ...

, relations of ideas are also similar to the so-called Truths of Reason, which are defined as those statements whose denials are self-contradictory.

References

David Hume {{Philo-stub