Rationalism

References

• Wikipedia Article on Rationalism

Notes

In philosophy, rationalism is the epistemological view that regards reason as the chief source and test of knowledge or any view appealing to reason as a source of knowledge or justification often in contrast to other possible sources of knowledge such as faith, tradition, or sensory experience. Rationalism is defined as a methodology or a theory in which the criterion of truth is deductive.

• In a major philosophical debate during the Enlightenment, rationalism (sometimes equated with innatism) was opposed to empiricism. On the one hand, the rationalists emphasized that knowledge is primarily innate and the intellect, the inner faculty of the human mind, can therefore directly grasp or derive logical truths; on the other hand, the empiricists emphasized that knowledge is not primarily innate and is best gained by careful observation of the physical world outside the mind, namely though sensory experiences.
• rationalists asserted that certain principles exist in logic, mathematics, ethics, and metaphysics that are so fundamentally true that denying them causes one to fall into contradiction.

Background

• Rationalism - as an appeal to human reason as a way of obtaining knowledge - has a philosophical history dating from antiquity.
• Since the Enlightenment, rationalism is usually associated with the introduction of mathematical methods into philosophy as seen in the works of Descartes, Leibniz, and Spinoza.
• Proponents of some varieties of rationalism argue that, starting with foundational basic principles, like the axioms of geometry, one could derive the rest of all possible knowledge.
• Rationalism, a methodology, became socially conflated with atheism, a worldview, in the 17th and 18th centuries.

Philosophical Usage

• The rationalist believes we come to knowledge a priori - through the use of logic - and is thus independent of sensory experience.
• Rationalism and empiricism are under the umbrella of epistemology. The argument between the two philosophies lies in the understanding of the warrant, which is under the wider epistemic umbrella of the theory of justification.
• • Loosely speaking, justification is the reason that someone (probably) holds a belief.
• At a core, rationalism consists of three claims:
• • the intuition/deduction thesis
  • • Some propositions in a particular subject area, S, are knowable by us by intuition alone; still others are knowable by being deduced from intuited propositions
    • Intuition is a a priori knowledge or experiential belief characterized by its immediacy, a form of rational insight.
    • Deduction is the process of reasoning from one or more general premises to reach a logically certain conclusion.
    • Some rationalists understand warranted beliefs to be beyond even the slightest doubt, others are more conservative and understand the warrant to be belief beyond a reasonable doubt.
  • the innate knowledge thesis
  • • We have knowledge of some truths in a particular subject area, S, as part of our rational nature
    • Rationalists argue that experiences can bring our rational nature into consciousness.
    • By claiming that knowledge is already with us, either consciously or unconsciously, a rationalist claims we don't really learn things in the traditional usage of the word, but rather that we simply use words we know.
  • the innate concept thesis
  • • We have some of the concepts we employ in a particular subject area, S, as part of our rational nature
    • The Innate Concept thesis suggests that some concepts are simply part of our rational nature.
• Optional claims:
• • the Indispensability of Reason
  • • The knowledge we gain in a subject area, S, by intuition and deduction, as well as the ideas and instances of knowledge in S that are innate to us, could not have been gained through sense experience
  • the Superiority of Reason
  • • The knowledge we gain in subject area S by intuition and deduction or have innately is superior to any knowledge gained by sense experience

History

Rationalist Philosophy in Western Antiquity

• Philosophers of this time laid down the foundations of rationalism. In particular, the understanding that we may be aware of knowledge available only through the use of rational thought.
• Pythagoras (570-495 BCE)
• • Pythagoras was one of the first Western philosophers to stress rational insight.
• Plato (427-347 BCE)
• • Plato held rational insight to a very high standard, as is seen in his works such as Meno and The Republic.
  • He taught on the Theory of Forms which asserts that the highest and most fundamental kind of reality is not the material world of change known to us through sensation, but rather the abstract, non-material world of forms (ideas).
• Aristotle (384-322 BCE)
• • Aristotle's main contribution to rationalist thinking was the use of syllogistic logic and its use in argument. Aristotle defines syllogism as a discourse in which certain (specific) things have been supposed, something different from the things supposed results of necessity because these things are so.

Middle Ages

• After Aristotle's death, Western rationalistic thought was generally characterized by its application to theology, such as in the works of Augustine, Avicenna, Averroes, and Maimonides.
• A notable event is the attempted merging of Greek rationalism with Christian revelation by Thomas Aquinas in the 13th century.
• Generally, the Roman Catholic Church viewed rationalists as a threat.

Classical Rationalism

• Rene Descartes (1596-1650)
• • Descartes was the first of the modern rationalists and has been dubbed the Father of Modern Philosophy.
  • Descartes thought that only knowledge of eternal truths - including the truths of mathematics, and the epistemological and metaphysical foundations of the sciences - could be attained by reason alone; other knowledge, the knowledge of physics, required experience of the world, aided by the scientific method.
  • He argued that since conscious sense experience can be the cause of illusions, then sense experience itself can be doubtable.
  • Descartes deduced that a rational pursuit of truth should doubt every belief about sensory reality.
  • His famous dictum, cognito ergo sum, or I think, therefore I am, is a conclusion reached a priori, prior to any kind of experience on the matter. The simple meaning is that doubting one's existence, in and of itself, proves that an I exists to do the thinking. In other words, doubting one's own doubting is absurd.

• Baruch Spinoza (1632-1677)
• • The philosophy of Baruch Spinoza is a systematic, logical, rational philosophy developed in seventeenth-century Europe. Spinoza's philosophy is a system of ideas constructed upon basic building blocks with an internal consistency with which he tried to answer life's major questions and in which he proposed that God exists only philosophically.
  • Many of his ideas on emotion have implications for modern psychology.
  • Spinoza's philosophy attracted believers such as Albert Einstein.
• Gottdfried Leibniz (1646-1716)
• • Leibniz was the last major figure of seventeenth-century rationalism who contributed heavily to other fields such as metaphysics, epistemology, logic, mathematics, physics, jurisprudence, and the philosophy of religion.
  • Leibniz rejected the existence of the material world. In Leibniz's view, there are infinitely many simple substances, which he called monads
  • Monads are the fundamental unit of reality, according to Leibniz, constituting both inanimate and animate objects. These units of reality represent the universe, though they are not subject to the laws of causality or space.
• Immanuel Kant (1724-1804)
• • Kant is one of the central figures of modern philosophy. He argues that human perception structures natural laws, and that reason is the source of morality.
  • Kant argued that pure reason is flawed when it goes beyond its limits and claims to know those things that are necessarily beyond the realm of every possible experience: the existence of God, free will, and the immorality of the human soul.
  • He argues that those objects beyond all possible experience by definition means that we cannot know them.
  • He argues that reason is necessary for processing that experience into coherent thought. He concludes that both reason and experience are necessary for human knowledge.

Contemporary Rationalism

• Rationalism has become a rarer label of philosophers today.
• Some people on the internet claim they are rationalists.

Criticism

• Proponents of emotional choice theory criticize rationalism, pointing out that the rationalist paradigm is generally based on the assumption that decision making is a conscious and reflective process based on thoughts and beliefs.
• However, cumulative research in neuroscience suggests that only a small part of the brain's activities operate at the level of conscious reflection. The vast majority of its activities consist of unconscious appraisals and emotions.
• The significance of emotions in decision-making has generally been ignored by rationalism, according to these critics.