03 Rationalism

Rationalism vs. Empiricism Debate

• This debate focuses on how we gain knowledge, particularly about the external world, with rationalists emphasizing reason and empiricists prioritizing sense experience.
• The distinction between rationalism and empiricism is not clear-cut; some, like Descartes, display both rationalist and empiricist tendencies.
• Empiricism acknowledges the role of reason in epistemology, just as rationalists accept the necessity of sensory experiences for acquiring knowledge.
• The debate between empiricism and rationalism centers on the importance and nature of the roles of experience versus reason.

Rationalist View

• Some concepts and knowledge are independent of sense experience.
• Knowledge can be gained through intuition (direct insight) and deduction (logical reasoning).
• The distinction between rationalism and empiricism is not clear-cut; some, like Descartes, display both rationalist and empiricist tendencies.
• Three categories of knowledge: knowledge of the external world, knowledge of the internal world or self-knowledge, and knowledge of moral and/or aesthetical values

Empiricist View

• Knowledge is primarily derived from sensory experience (both sense and reflective).
• Empiricists counter rationalists by explaining how experience alone provides the knowledge rationalists claim, and that reflective understanding can fill in gaps.

Key Concepts in Rationalism

• What is the nature of propositional knowledge (knowledge that a particular proposition about the world, ourselves, morality, or beauty is true)?
  • Propositional knowledge requires belief, truth, and an additional element called "warrant," which distinguishes knowledge from a lucky guess.
  • warrant: the justification of a belief that raises its epistemic status from mere belief to “warranted as” knowledge by evidence.
• How can we gain knowledge?
  • We can form true beliefs through luck, but gaining warranted beliefs is more complex and unclear.
• What are the limits of our knowledge?
  • Some aspects of the external world, ourselves, or the moral and aesthetical values may be within the limits of our thought but beyond the limits of our knowledge.
  • beyond limits of our knowledge: cannot know which description is true
  • beyond limits of our thought: cannot form intelligible descriptions of them
• The rationalism vs. empiricism debate focuses on the second question - the sources of concepts and knowledge, with implications for other philosophical questions.

Intuition/Deduction Thesis

• Intuition/Deduction Thesis: Some knowledge is known through direct intuition or deduced logically without relying on experience. (agreed by both schools)
• Intuition is a direct, immediate insight similar to internal perception, allowing us to "see" propositions as true.
• Deduction is deriving conclusions from intuited premises through valid arguments, leading to a priori knowledge independent of experience.
• Criticism: Requiring certainty for knowledge is problematic, as it excludes much of what we commonly consider knowledge.
• Leibniz's Argument: Experience only provides particular truths (instances), not the universal necessity needed for certain knowledge (e.g., in mathematics).
  • Necessary truths (like those in math) must come from intuition and deduction, not sense experience.
  • Leibniz supports the Innate Knowledge Thesis, but his argument can also relate to the Intuition/Deduction Thesis.
• Intuition vs. Experience: Intuition provides knowledge beyond what experience can offer, especially in areas like logic, metaphysics, and morals.
• Key Challenge: Defenders of the Intuition/Deduction Thesis must clarify what intuition is and how it provides warranted true beliefs about the external world.
• Metaphors insufficient: Simply describing intuition as intellectual "grasping" or "seeing" doesn't explain how it leads to knowledge about the world.

Innate Knowledge Thesis

• Innate Knowledge Thesis: We possess certain truths inherently as part of our nature, not acquired through experience or intuition/deduction.
• Experiences may trigger awareness of innate knowledge but do not provide the knowledge itself.
• Different rationalists believe innate knowledge comes from prior existence, divine provision, or natural selection.
• Plato's Doctrine of Recollection: Knowledge is recollected from a previous life where we had direct access to abstract truths (e.g., mathematics).
• Modern Perspective: Few support Plato's view today, but many adopt forms of innate knowledge due to the lack of adequate explanations for certain knowledge gained without experience.
• Carruthers' View: Evolutionary selection determines our innate knowledge, which emerges at specific life stages. Experience triggers belief but doesn't provide the knowledge itself.
• Problem: How can innate beliefs be warranted if they are not based on experience, intuition, or deduction? Rationalists argue these beliefs are warranted despite not deriving from these sources.

Innate Concept Thesis

• Innate Concept Thesis: Some concepts are inherent in our rational nature and are not derived from experience.
• While experiences can bring these innate concepts to consciousness, they do not supply or define the content of the concepts.
• Descartes’ View: He divides ideas into three categories:
  • Adventitious (gained through experience, like heat),
  • Invented (created by combining existing ideas, like a hippogriff),
  • Innate (placed in our minds by God, like the concepts of God or perfect geometry).
• Example: Descartes argues that the concept of an infinitely perfect being (God) cannot be derived from experience, as experience only provides limited concepts of finite beings.

• Locke’s Empiricist Response:

  • Argues against the existence of innate concepts, noting that people (e.g., children or those from different cultures) do not consciously entertain the concept of God.
  • Claims that experience can account for all our concepts, including those thought to be innate, without the need for innate concepts.

• Intuition/Deduction thesis is equally important to empiricism. The key difference between rationalists and empiricists regarding the Intuition/Deduction Thesis is the source of intuitions:

  • For rationalists, intuitions are largely innate.
  • For empiricists like Locke, intuitions are derived from sensory experiences.
• Rationalism centers on two key theses: the Innate Knowledge Thesis (innate knowledge of propositions) and the Innate Concept Thesis (innate knowledge of concepts).
• Rationalists adjust the strength of their view based on how they define warrant:
  • Some argue intuition leads to absolutely certain beliefs.
  • Others hold intuition provides beliefs that are beyond reasonable doubt but not infallible.
• Indispensability of Reason Thesis: Knowledge from reason (intuition and deduction) cannot be obtained through sense experience.
• Superiority of Reason Thesis: Knowledge from reason is superior to knowledge gained from sense experience.

• Descartes, for example, claimed that knowledge from intuition is absolutely certain, while sense experience-based knowledge has some degree of uncertainty.

• Philosophical Examples:

  • Descartes is often cited as a rationalist, emphasizing the role of intuition and reason in knowing certain truths (e.g., the existence of God).
  • Empiricists like Locke counter that all knowledge can be traced to experience, even complex ideas like the concept of God.