PAPER NO. 72

WHAT IS KNOWLEDGE?

Epistemology (the logos of episteme) is concerned with an account of knowledge regarding the certainty of basic beliefs. The term ‘knowledge’ is ambiguous; there are various ways in which ‘knowledge’ can be understood. It is the final sense below—justified true belief—that is of primary importance in addressing contemporary challenges in epistemology.

  1. Knowledge by acquaintance is direct, or non-inferential, sense perception of a thing, or the properties of a thing. For example: the taste of a lemon, the smell of a rose, or the color of blue.
  2. Factual knowledge is the comprehension of some “fact.” For example: ‘I know that today is Tuesday.’ Know-how is the comprehension of how to execute a task. For example: ‘I know how to ride a bicycle.’
  3. A priori knowledge is propositional knowledge independent of sense perception. For example: ‘All bachelors are unmarried men.’ A posteriori knowledge is propositional knowledge that is dependent upon the senses. For example: ‘The sun is shining today.’
  4. Propositional knowledge is understanding the meaning of a judgment (S is P), affirming the content of that judgment, and having logical inferential support for the truth claim of that judgment. For example: ‘I know that something is eternal.’
  5. In attempting to define propositional knowledge, Plato says that knowledge is true opinion with an account. Contemporary philosophers, claiming to follow Plato, define knowledge as: justified true belief. This definition of knowledge may be stated more formally by saying:

A person S knows a proposition p if and only if:

  1. p is true
  2. S believes p
  3. S is justified in believing that p
  1. To have a belief is to have a mental affirmation of a proposition. Consider the existential state of holding a belief.

Truth is what corresponds with reality. Consider the difference between a subjective and objective definition of truth.

Justification is what guarantees true belief.

  1. The three conditions (of justified, true, belief) are said to be necessary and sufficient for knowledge. These conditions have been challenged as being neither necessary nor sufficient for knowledge.

    1. Edmund Gettier, through his counterexamples, challenges the sufficiency of justification for knowledge.
    2. Alvin Plantinga, in response to challenges to the sufficiency of justification, restates the definition of knowledge as warranted true belief, and denies the necessity of justification for knowledge.
  2. The challenge is plausible only until an ambiguity in understanding the third condition of justification is clarified, and by addressing primary (logically basic), rather than secondary (properly basic), beliefs.
  3. We may retain the justified true belief formulation of knowledge by removing the ambiguity between Plato’s rationalist account and Gettier and Plantinga’s empiricist accounts. Knowledge is justified true belief where:

    1. Weak justification is sensory data that provides a high probability of truth (sufficient for most of our everyday judgments). This does not guarantee knowledge.
    2. Strong justification is by reason and argument such that the opposite is impossible (necessary for foundational philosophical claims). Strong justification requires an understanding of reason (see Paper No. 5 and Paper No. 75). This guarantees knowledge.
  4. To believe the conclusion of a sound argument because the argument is seen as sound is to possess knowledge.

This paper is posthumously published based upon the original work of Dr. Surrendra Gangadean

and has been edited by The Logos Foundation editorial board.


© 2005/2022 Logos Papers Press