Defining Truth: Correspondence, Coherence, and Scientific Methods

The Philosophical Problem of Truth

Truth Concerning Reality: Appearance vs. Essence

The term “truth” can be identified here with true reality as opposed to mere appearance. The distinction between reality and appearance has been the subject of a long debate throughout the history of philosophy. This debate has often been dominated by the conception that appearances are concealments of reality.

Things are often not as they appear. For example, objects do not become smaller when they move away, and a stick does not bend when it is immersed in water. Appearances are deceptive and hide the true reality, since we cannot always see how things are in reality.

Truth Concerning Knowledge

The concept of truth can also be applied to propositions and knowledge claims, leading to several distinct theories:

Truth as Correspondence

This theory considers that a proposition is true when there is a fit or correspondence between what the proposition expresses and the reality it concerns.

Truth as Coherence

This theory considers that a proposition is true if it is not inconsistent with the rest of the accepted propositions within a given system, rather than by its correspondence with external reality.

Truth as Success (Pragmatism)

This theory considers that a proposition is true when it is useful and, therefore, leads to success. A proposition is true if its implementation has positive results and it is false if the consequences are negative.

Criteria for Recognizing Truth

How do we determine if a proposition is true? Philosophers have proposed several criteria:

The Criterion of Authority

According to this criterion, something is accepted as true if it has been said by someone or something considered an authority in a subject or a community leader. This acceptance is based purely on the trust and respect that person or institution inspires. We accept what they say uncritically, often finding it unthinkable that they could be wrong.

The Criterion of Evidence

The term "evidence" refers to the special way in which certain facts and propositions are shown, leading us to consider the knowledge as “obvious.” Knowledge is evident when it produces a certainty that prevents us from doubting its truth. However, this approach suffers from some subjectivity, because this sense of certainty and security is actually a mental state (a feeling).

The Criterion of Intersubjectivity

This criterion states that our beliefs, to be admitted as true and provide knowledge, must be acceptable to any rational subject. This point of view is based on the idea that knowledge is objective, and therefore shareable by all and not exclusive to a particular person. Compared to the criterion of evidence, intersubjectivity has the advantage of being based not only on the recognition of truth made by one subject, but on the recognition of many, thus offering more guarantees of success.

The Classification of Sciences

Sciences are typically categorized based on their methodology and object of study:

Formal Sciences

Formal sciences are not based on observation, but rather on the internal coherence and logical consistency of the system. Examples include Mathematics and Logic.

Empirical Sciences

Empirical sciences deal with reality; that is, with the events that occur in the world and the relationships between them. This knowledge is derived from observation and experimentation.

Natural Sciences

These disciplines deal specifically with natural reality (e.g., Physics, Biology, Chemistry).

Social Sciences

These disciplines deal specifically with social and human reality (e.g., Sociology, Psychology, Economics).