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5.3: Truth and Scientific Truth

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  • Truth Overview

    There are several different theories of what truth is. It turns out that as with most questions in philosophy, the question “what is truth?” Does not have a simple answer.

    The conformity of a proposition to the way things are. Precise analysis of the nature of truth is the subject of the correspondence, coherence, pragmatic, redundancy, and semantic theories of truth.

    Theories of Truth

    Correspondence Theory of Truth

    This is the theory most people are brought up to believe but it has too many problems with it to be the complete answer. A claim is made about the universe. We go and check out the claim with observations and physical measuring devices. This is understood by many people in the simplest way. A claim is made about the physical universe and people want to go and check it out. Is that so for all claims?

    The theory is based on the belief that a proposition is true when it conforms with some fact or state of affairs. While this theory properly emphasizes the notion that propositions are true when they correspond to reality, its proponents often have difficulty explaining what facts are and how propositions are related to them.

    • There exists an independent realm of facts: reality
    • Truth is the correspondence of belief with fact
    • Belief corresponds to facts = truth
    • Belief does not correspond to facts = false
    Correspondence Theory of Truth

    Verification involves subjective experiences as to both observations and require interpretations.

    Example 1:

    Claims are made about things that are very large; such as galaxies and the entire universe, as to its shape and size and duration that are beyond the ability of any human to have a direct experience of it.

    Example 2:

    Claims are made about things that are very small such as sub atomic particles and small quanta of energy, bosons, gluons, neutrinos, charm particles and the like which no human can have a direct experience of.

    Example 3:

    A simple claim: There is a container of milk in the refrigerator.

    To determine whether or not this is true all one needs to do is to go to the refrigerator and check. Would the claim be true if:

    1. There is a bottle of milk there?
    2. There is a wax container of milk there.
    3. There is a wax container of powdered milk there?
    4. There is a wax container of parmalat there?

    Some answer yes it would be true in all 4 cases. Some think it is only true in case B. It all depends on what you mean by "container." For some, it means a wax container. For others, it may mean any object that holds any sort of contents.

    Example 4

    Is the following claim true or not?

    Bill Clinton: “I did not have sexual relations with that woman," i.e. Monica Lewinski.

    It all depends on what you mean by "sex". For some, it means any act involving the sexual organs being stimulated to the point of organs. For others, it might mean only the penetration of the penis into a vagina and only for beings of the same species.

    Coherence Theory of Truth

    This explains how scientists can make claims about the very large and small objects using a system of claims already accepted to be true.

    The theory is the belief that a proposition is true to the extent that it agrees with other true propositions. In contrast with the correspondence theory's emphasis on an independent reality, this view supposes that reliable beliefs constitute an inter-related system, each element of which entails every other.

    From Correspondence to Coherence
    • Truth is a property of a related group of consistent statements
    • Truth is a property of a related group of consistent statements
    1. What if other judgments (statements) are false? Consistent error is possible?
    2. Coherence theory in the last analysis seems to involve a correspondence for the first judgments must be verified directly. How?

    Pragmatic Theory of Truth

    This theory is the belief that a proposition is true when acting upon it yields satisfactory practical results. As formulated by William James, the pragmatic theory promises (in the long term) a convergence of human opinions upon a stable body of scientific propositions that have been shown in experience to be successful principles for human action.

    Examines how beliefs work in practice, the practical difference. Truth of a belief is determined by evaluating how well the belief satisfies the whole of human nature over a long period of time: How well does it work? What are its consequences?

    Pragmatic Theory of Truth-A Problem to be Solved
    1. What is justified for one community to believe may not be true!!!!
    2. How to explain errors? Falsehoods?
    3. It makes truth relative.
      1. No absolute truth.
      2. No objective truth.
      3. Many truths at once!
    4. Self-refuting basic claims:

    The pragmatic theory makes the claims that :

    1. There is no objective knowledge
    2. There is no absolute knowledge
    3. There is no objective truth
    4. There is no absolute truth

    If these claims are true then they would refute themselves. If all claims are true only within a community that accepts them as true then the claims above (a to d) are only true within the communities that accept them as being true by whatever criteria they use and think has been satisfied. So within the community of pragmatists the claims would be true but for others they would not be true and thus there is affirmed a series of contradictions.

    Pragmatists would by their principles and theories accept that claims above (a to d) are true and not true at the same time! Pragmatists overlook a number of things. There are different types of claims and it is only the empirical, aesthetic, and ethical claims that appear to be troublesome. The empirical claims can be resolved as to their accuracy. This is so because there is a difference between truth and justified belief which pragmatism overlooks.

    C.S. Pierce’s solution was to postulate an ideal community of inquirers who would come to agreement concerning what is known and what is true in the infinite long run of time. C. S. Pierce held that there was but one reality. Truth is what an ideal community would believe in the long run of time.This is particularly true for empirical claims.

    However there are many post modernist pragmatists who have abandoned the idea of an objective truth and objective knowledge.

    Rorty thus is emphasizing the nature of all human knowledge as "made" rather than "found." Rorty is mostly content to point out the fallacy of trying to pursue objective reality. His makes truth something that is psychological. What difference do the beliefs make if they are true? Truth is whatever has met a society's criteria for justification. For pragmatists like Richard Rorty, there is no objective truth at all. All claims need only satisfy the group’s expectations for verification. Science is just one of many groups with its own rules and criteria. As there are multiple groups with different criteria there can be multiple truths.

    This makes truth something that is psychological. What difference do the beliefs make if they are true? Truth is whatever has met a society's criteria for justification. For pragmatists like Richard Rorty, there is no objective truth at all. All claims need only satisfy the group’s expectations for verification. Science is just one of many groups with its own rules and criteria. As there are multiple groups with different criteria there can be multiple truths.

    Logical Empiricism

    For the logical empiricist movement the truth of a proposition rests on how well it is verified. For them what makes a proposition true or false would be how well it checks out through a process of verification.

    The answer is that we test the validity of an empirical hypothesis by seeing whether it actually fulfills the function which it is designed to fulfill. And we have seen that the function of an empirical hypothesis is to enable us to anticipate experience. Accordingly, if an observation to which a given proposition is relevant conforms to our expectations, the truth of that proposition is confirmed. There is no certainty in this operation. If the experiment comes off according to expectations then credibility has been enhanced. There is no question that it will be repeated. If it does not, then questions about the experiment may be raised; if it is successful again, greater probability of being true is attached to the statement.

    Thus the best that is offered is that at the present time a proposition would have a certain amount of support and of verification.

    Does Truth Matter?

    If objectivity is rejected, every groups claims would be equal. So the claims of the following ideologies would be true: racism, sexism, Nazism, etc... According to this post modern theory of truth all claims are ideologies. Must all claims be accepted as true at once?

    With empirical claims how can it be that there would not be some basis for truth that would rule out inconsistent and contradictory claims from all being true at once? How could it be true that the earth would be flat and spherical at the same time?

    Even with claims about non-physical entities, how could it be that there are more than one truth as when:

    • Group A thinks it is true that people have souls
    • Group B thinks that there are no souls

    How can the claims to truth for both group A and group B be true at the same time?

    Does Truth Matter?- Carl Sagan

    Truth, Conflicts, and Power

    Must we tolerate and respect all groups even those with conflicting claims? How is it to be resolved when there are conflicts? For the pragmatists, all the criteria for resolution are criteria that groups have developed. It will then always come down to which group has the most power. For pragmatists and postmodern thinkers: power is knowledge

    There is a cynicism with pragmatists such as Rorty and other post modernists who would deny that there is "truth" as objective. They claim that truth is only and whatever those in power have persuaded people to believe. They accept that truth is whatever experts happen to agree upon but not that it relates to anything that is "objective". They make truth something based on the consent or agreement of the folks who wish to claim that truth. Such cynics make truth depend on nothing "objective" and deny that there is anything that is "objective". The resolution of conflicting claims concerning what is true lies not in any reference to an objective reality or to an objective truth but to whatever criteria the group holds for the resolution of claims. If two groups have two different sets of criteria then the group with the most power will determine what truth is by its criteria and impose it upon the others who will go on thinking that their original ideas were true anyway. There will be two truths at once over the same situation. This will apply to claims as to what is real as well as to what is true.

    One group may use the scientific method and hold to the criteria of science and another group may use consultation with a shaman and the shaman's mystical experiences as the basis for truth and the results of each approach are thought to be the truth by each group and for the pragmatists both are correct at the same time. A large rock in the American museum of natural history can be a meteorite for the group using science and a messenger from the sky god for the original peoples at the same time.

    It can be true for one group that (Jews, blacks, and women) are inferior to (Christians, whites, or men) and for another group the opposite can be true at the same time according to this theory. One of the values that pragmatists attempt to promote is tolerance and in the name of tolerance and for the sake of tolerance people are asked to respect the right of others to hold their own views. Yet if a person holds the view that tolerance is wrong then they can be right and tolerance can be both good and bad at the same time. This theory results in applications of political power to resolve conflicts and has not lead to a more tolerant set of societies in this world.

    Philosophy and the Truth

    Redundancy Theory of Truth

    Belief that it is always logically superfluous to claim that a proposition is true, since this claim adds nothing further to a simple affirmation of the proposition itself. "It is true that I am bald." means the same thing as "I am bald."

    Why Truth Matters?

    Truth has fallen victim to a proliferation of behaviors that diminish the importance of truth in popular culture. Among the behaviors are the increase in use of what is known as "truthiness" and "bullshit" as well as denialism and postmodern ideas of relativism, denying that there is or can be truth.

    On Bullshit

    In his essay On Bullshit (originally written in 1986, and published as a monograph in 2005), philosopher Harry Frankfurt of Princeton University characterizes bullshit as a form of falsehood distinct from lying. The liar, Frankfurt holds, knows and cares about the truth, but deliberately sets out to mislead instead of telling the truth. The "bullshitter", on the other hand, does not care about the truth and is only seeking to impress.

    Is it impossible for someone to lie unless he thinks he knows the truth. Producing bullshit requires no such conviction. A person who lies is thereby responding to the truth, and he is to that extent respectful of it. When an honest man speaks, he says only what he believes to be true; and for the liar, it is correspondingly indispensable that he considers his statements to be false. For the bullshitter, however, all these bets are off: he is neither on the side of the true nor on the side of the false. His eye is not on the facts at all, as the eyes of the honest man and of the liar are, except insofar as they may be pertinent to his interest in getting away with what he says. He does not care whether the things he says describe reality correctly. He just picks them out, or makes them up, to suit his purpose.


    In Science, denialism has been defined as the rejection of basic concepts that are undisputed and well-supported parts of the scientific consensus on a topic in favor of ideas that are both radical and controversial. It has been proposed that the various forms of denialism have the common feature of the rejection of overwhelming evidence and the generation of a controversy through attempts to deny that a consensus exists. A common example is young earth creationism and its dispute with the evolutionary theory.

    The terms Holocaust denialism and AIDS denialism have been used and the term climate change denialists has been applied to those who argue against the scientific consensus that global warming is occurring and that human activity is its primary cause. Use of the word denialism has been criticized, for example as a polemical propaganda tool to suppress non-mainstream views. Similarly, in an essay discussing the general importance of skepticism, Clive James objected to the use of the word denialist to describe climate change skeptics, stating that it "calls up the spectacle of a fanatic denying the Holocaust." Celia Farber has objected to the term AIDS denialists arguing that it is unjustifiable to place this belief on the same moral level with the Nazi crimes against humanity. However, Robert Gallo et al. Defended this latter comparison, stating that AIDS denialism is similar to Holocaust denial as it is a form of pseudoscience that "contradicts an immense body of research."

    Several motivations for denialism have been proposed, including religious beliefs and self-interest, or as a psychological defense mechanism against disturbing ideas.

    Relativism is the concept that points of view have no absolute truth or validity, having only relative, subjective value according to differences in perception and consideration. The term is often used to refer to the context of moral principle, where in a relativistic mode of thought, principles and ethics are regarded as applicable in only limited context. There are many forms of relativism which vary in their degree of controversy. The term often refers to truth relativism, which is the doctrine that there are no absolute truths, i.e., that truth is always relative to some particular frame of reference, such as a language or a culture. Another widespread and contentious form is moral relativism.

    There is a cynicism regarding truth or objective truth. There also exists the desire to believe what is useful to believe and to believe that what matters are the consequences. In reaction to this there is not to be a promotion of truth that is conservative in advocating an allegiance to you beliefs. This is not truth but dogma. There is not to be support for the liberal equation of truth with absolute certain truth. This then would promote relativism.

    Truth Does Matter

    Without truth there is no support for outrage over atrocities if all reports are of equal truth value and treated as just text. Truth and its pursuit are politically important especially the need to distinguish right answers from wrong answers, true from false reports about the world

    1. If there is no truth or if all truth is relative then
      1. Criticisms are not permissible
      2. Dissent is not permissible or supportable
    2. The idea of a fundamental right or human right is undermined as they presuppose some idea of truth.
    3. Truth is a necessary condition asserting the existence of any human right apart from what government decrees
    4. Truth is necessary to reject the idea that believing in claim x makes claim x true.

    It follows that a necessary condition for fundamental rights is a distinction between what the government -- in the wide sense of the term -- says is so and what is true. That is, in order for me to understand that I have fundamental rights, it must be possible for me to have the following thought: that even though everyone else in my community thinks that, for example, same-sex marriages should be outlawed, people of the same sex still have a right to be married. But I couldn't have that thought unless I was able to entertain the idea that believing doesn't make things so, that there is something that my thoughts can respond to other than the views of my fellow citizens, powerful or not. The very concept of a fundamental right, presupposes the concept of truth. Take-home lesson: if you care about your rights, you had better care about truth.

    • Governmental transparency and freedom of information are the basis of a defense against tyranny.
    • Truth is important for the integrity of the democratic process.

    But the anti-tyranny argument will be of interest to those whose government is not yet tyrannical, but who fear it is heading in that direction. In brief, the anti-tyranny argument is precisely the sort of argument that is of interest to concerned citizens of a liberal democracy like our own. Unless the government strives to tell the truth, liberal democracies are no longer liberal or democratic.

    Caring about truth provides a ground and a motivation for our curiosity about the facts and for our commitment to the importance of inquiry. Certain aspects of our experience make it apparent that they are independent of us. That is the origin of our concept of reality, which is essentially a concept of what limits us, of what we cannot alter or control by the mere motion of our will. We learn our powers and our vulnerabilities.

    It is only through our recognition of a world of stubbornly independent of reality, fact and truth that we come both to recognize ourselves as being distinct from others and to articulate the specific nature of our own identities.

    Scientific Truth

    For logical, semantic, and systemic claims there are methods to determine their truth. It is with regard to the empirical claims about the universe, events and properties of it that is the main concern of the theories about truth. Perhaps the best that humans have been able to do with regard to getting at the truth concerning empirical claims is the development of a method for doing it. In Science there are a number of views that are operative in its various phases.

    1. Instrumentalist view - pragmatist theory

    The scientific theory makes predictions; the predictions are verified and so it works and it satisfies the community of inquirers (the scientists).

    1. The realist view - correspondence theory

    The scientific theory provides true explanations because its predictions are verified through empirical testing.

    1. The conceptual relativist - coherence theory

    The scientific theory is coherent within a given framework, which coheres or fits in with a system of beliefs

    True theory is that which is accepted by the community of working scientists with its own conceptual framework. Independent checks are not possible because all observations are theory laden. So in the end perhaps the truth concerning empirical claims is that claim which:

    • Corresponds to fact and
    • Coheres with and is consistent with other established truths and
    • Has useful consequences for those concerned.

    Perhaps what is the most useful consequence of a belief concerning an empirical claim is to correspond to reality (facts) and to cohere (be consistent) with what has already been accepted as true by the same means.

    Philosophers shall continue to spend time arriving at a more certain foundation for claims of truth. For now what do we have? What is knowledge? To claim to know and to have that claim accepted by others as being correct is to satisfy the criteria that the claim be warranted. What supplies the warrant is that the claim be justified and true. How is that accomplished or established? Well that depends on the type of claim that it is:

    1. Semantic claim: supported by references to dictionaries or lexicons
    2. Systemic claim: supported by the rules of the system in which the claim is being made
    3. Logical claim: supported by and consistent with the rules of logic
    4. Empirical claim: supported by a process of verification that establishes that the empirical claim.
      1. Corresponds to fact and
      2. Coheres with and is consistent with other established truths and
      3. Has useful consequences for those concerned.

    This may be the best explanation that humans have for what and how they know what they claim to know. It is not totally satisfying to all critical inquirers but it is more well founded within human experience than the position that there is no knowledge at all or that there is no knowledge that is objective or that there is no knowledge that is certain. There are types or forms of knowledge and within each there are the means to establish the justification for making and accepting claims.