Critical thinking involves reflection on our beliefs, in order to increase our awareness of them, and the evaluation of these beliefs, in order to assess our evidence for them.

Truth and values should be grounded in one’s own experience, in one’s own ability to think and choose, but this must be accomplished in natural, social and historical context. Human knowledge properly speaking involves a relationship between the individual and the world and between the individual and other individuals within social and historical context. Thus, truth and values should be grounded in one’s own concrete experience, yet we must also check our own experiences of the world against each other and against the experiences lived through by others, both past and present.

When reading critically, the reader should make a genuine attempt to understand the author’s position, yet the reader should also attempt to listen to his or her own response to the material being read. Do you agree or disagree with the author’s claims? If you do agree or disagree, why? This is a good place to begin if you wish to write critically about what you have read. Start by stating whether you agree or disagree, and then proceed to state the reasons why you do so. To begin, you may wish to simply imagine that you are trying to convince a friend of your claim: just state as calmly and as clearly as you can your reasons for your agreement or disagreement. Knowing the principles of logic, both inductive and deductive, will help you develop your intuitive reasons into more formal and precise arguments. Thus knowing the principles of logic will help you both state your own position and evaluate the works of others more rationally.

Before moving on to discuss the logical principles of sound reasoning a few additional points should be mentioned that may help you evaluate a position.

First of all, try your best to recognize the position’s assumptions and consequences. What is the author’s starting point, and what does this starting point assume? Moreover, what are the consequences of holding this position? For example, if someone argues for the death penalty, does this position assume that some people are inherently malevolent and cannot change? Or does the death penalty have, as evidence indicates, an unfair consequence for certain racial or ethnic groups? Knowing a positions assumptions and consequences will help you begin to evaluate this position.

Secondly, what bias does the author hold, either explicitly or implicitly?

Is the author a conservative trying to make a case against liberalism? Or is the author a liberal trying to make a case against the conservative position? Or perhaps the author’s position lies somewhere in between. Knowing where someone is coming from may help evaluate the position being asserted, for it helps gain greater insight into the positions assumptions and consequences.

Obviously, it is always best to read more than one author or position when researching an issue. It is always best to read the range of positions and how they criticize one another.  The reader is then in a better position to choose the best explanation or to formulate one that is better. Academic sources tend to be the best because within academia positions are usually carefully reviewed and criticized. They tend to be reviewed and evaluated by peers within the field. There are no unbiased positions, but academic sources move toward being unbiased because they are scrutinized and cross-checked more than other sources, certainly more than the typical popular source.

Thirdly, does the author use a neutral language that attempts to carefully and accurately describe what has occurred or a language that contains emotional and evocative expressions? The “spinning” or manipulation of the emotional content of language can be a powerful tool of persuasion, for calling someone a “freedom fighter” rather than a “terrorist,” or vice versa, can easily predispose an audience to one interpretation rather than another. While there is some debate about this, and while most believe there is no completely objective language, many philosophers believe that we can use language more neutrally in our attempt to describe our publicly perceived world more accurately. After all, describing the throwing of someone from a ten-story building as “providing the freedom to fly” makes far less sense and is far less accurate than describing it as “an act of killing.”

Fourthly, does the position (the explanation or theory) accurately describe and explain the facts or human experiences as they typically appear? While philosophers have moved away from the notion that things of a certain type (for example, all dogs) share an identical essence, most accept the idea that the individuals of a certain type are similar enough to construct meaningful class concepts about them, to construct concepts that more or less capture their similarity. We now know, for example, that no two human beings are identical (biologically, genetically, or psychologically), but we also know that human beings are similar enough for us to make reasonable generalizations about the basic conditions of a healthy life, the genetic probability of contracting, or not contracting, a certain disease, and about human behavior in certain typical circumstances. There may not be a single human essence that exactly and precisely determines human behavior forever, yet humans are similar enough to be able to make reasonable generalizations about the typical range of human reactions to various circumstances, both natural and social.

Moreover, if this is so, if the world and things within it, including humans, are stable enough to make reasonable generalizations about them, then these generalizations can be tested against future experiences and refined or changed if necessary. There is a relatively stable world around us, and it is generally experienced as public or accessible to others and not just as a product of one’s own cognition or wishes. While it is true that we experience this world through the filtering avenues of the human body and our culture, including our language, this does not mean that we can make the world anything we wish. There is something outside our bodily and culturally adaptive systems that helps measure and limit them, a relatively stable world whose materials and events can be described with greater or lesser accuracy. It is to the determination of this accuracy that we should now turn.