Critical Thinking

Evidence and credibility:

Introduction 
Critical thinking teaches the skills needed to analyse successfully and evaluate arguments.

Arguments are a reason or reasons that must support a conclusion. These ones are designed to persuade and convince the reader that your argument is true. In order to do this, we would need and evidence that supports the argument. However, in some cases evidence is not totally convincing and a judgement about the credibility of the evidence is needed. Credible means believable. If we know that the argument is credible, then we might accept it.

Sources of evidence:

Evidence is always the information we use to support any idea in an argument. This evidence comes from a source, which could be an eyewitness, a newspaper report, a scientific journal, and many more. It is very important always to assess the credibility of the source, because if not the source is useless.

Credibility criteria:

Critical thinking provides a number of techniques wich can be used to asses the credibility of sources and the evidence they provide.

Neutrality:

Something neutral is impartial. It does not lie, distort the evidence, or present information to support one side of a subject.

Vested Interest:

If an individual or an organisation has a vested interest, they have something to again from promoting and defending a particular point of view. This may lead them to lie, to select certain evidence and ignore or reject other evidence, and to disert evidence in order to benefit themselves. Is a vested interest can be shown, then this may reduce the credibility.

However, identifying a vested interest does not necessary reduce the credibility of a source.

Bias:

A vested interest can lead to bias. Bias means favouring a particular view, having a preference for something, seeing things in a particular way. Identifying bias can reduce the credibility of a source and the evidence they give.

Expertice:

When evidence is given by an expert, is always more credible. Their knowledge and skills makes us sure about what we are reading, we trust what they say from the experience they have. Nevertheless, sometimes experts get it wrong or the standards of expertise change over the years. Expertise is only credible when it's relevant.

Reputation:

Credibily is also based on a character's reputation. Generally, the higher the reputation of a source is, more credible it will be. However, an honesty and reliable reputation doesn't mean that the information provided is the correct one.

Observation and eyewitnes accounts:

An eyewitness is one of the most, or even the most, credible evidences.The eyewitness observes an event. Someone gives an account of the event, like re-telling it. Sometimes little details might be changed. As a result, hearsay evidence is seen.However, the credibility of the eyewitness has to be proved, since some factor could alternate the sequence of events seen.

Corroboration:

Pieces of evidence wich support each other. Corroboration inereases the credibility of evidence.

Selectivility and representativeness:

What kind of evidence is selected? Does it represent all sides of an issue or only one side?. Compaining groups like friend of the earth and greenpeace. Select only evidence wich support their views.This one-sided selection of evidence is seem to reduce their credibility as sources. It reflects their bias.The presentations of unrepresentative information can weaken the credibility of the source and the evidence they provide.

Context:

This is used to know the context of the evidence or event (setting or situation in  which the evidence is produced). It is important since from the context you can obtain identifying factors that might affect the evidence.

Credibility on truth:

Credible means believable, not true. True means correct and accurate. Evidence not always has to be true, to be credible. Credibility and truth are not equals at all.