There are a variety of definitions of critical thinking and no consensus on any one of them (Riddell 2007). This situation means we need to be careful about relying on any one definition. In essence, however, critical thinking refers to the activity of questioning what is usually taken for granted.

Whether we are aware of it or not, all behaviour is based on certain values, assumptions and beliefs. These form the basis for our decisions to act in certain ways. In a professional context such as nursing practice, everything that we think, say or do is the result of a complex web of beliefs, values and assumptions that have formed as a result of our life experiences. As we grow up in our family, attend school, participate in religious communities, associate with friends, watch television, read newspapers, and work for various employers, we develop a ‘pair of spectacles’ through which we understand and interpret the world and all that happens in it. Just as a person who wears glasses eventually becomes unaware that they are even wearing them, so too each of us adjusts to our worldview ‘spectacles’ until, often, we are completely unaware what values, beliefs and assumptions are influencing us in a specific situation.

Critical thinking means stopping and reflecting on the reasons for doing things the way they are done or for experiencing things the way they are—focusing on what is frequently taken for granted and evaluating the values, beliefs and assumptions that are held, and asking whether or not what is done and thought is justifiable or not. These characteristics of critical thinking imply a self-consciousness of what, how and why we are thinking, with the intention of improving thinking. In short, ‘critical thinking is thinking about your thinking while you’re thinking in order to make your thinking better’ (Paul 2008). Improving thinking is essential because it is intimately related to the many decisions that need to be made each day. The quality of our lives is determined by the quality of our decisions, and the quality of our decisions is determined by the quality of our reasoning (Schick & Vaughn 1995). In particular, ‘[i]f nurses are to deal effectively with complex change, increased demands and greater accountability, they must become skilled in higher level thinking and reasoning abilities’ (Simpson & Courtney 2002:89).

An important aspect of critical thinking is healthy scepticism. This scepticism is necessary because there are many attempts to persuade people to accept various claims. These attempts to persuade also occur in professional contexts. For example, research reports suggest changes to practice; peers argue that their way of acting is the right one; therapists promote various interventions; administrators argue that certain changes need to be made to the workplace; and so on. Often these claims are contradictory, so they cannot all be acceptable.

Practitioners need to sort through all these, often competing, claims. To accept them all without question will, at best, be highly confusing and, at worst, may endanger the lives of others if actions are based on wrong information or conclusions. To adopt an attitude of healthy scepticism means to cautiously listen to or read the claims that others make, carefully evaluating their legitimacy, and not rushing to accept a conclusion without careful thought.

The same rigorous thinking needs to be done about our own nursing practice. We make decisions every moment, which we assume are of benefit to our patients. Asking questions about the practices we engage in, including what evidence is available to support their efficacy, is essential if our nursing practice is to produce positive outcomes for those for whom we care.

Critical thinking is not the same as creative thinking. According to Miller and Babcock (1996:117), creative thinking is, among other things, more divergent, messy, unpredictable, provocative, spontaneous and playful than critical thinking. They describe critical thinking as selective, orderly, predictable, analytical, judgmental and evaluative.

Creative thinking, although different from critical thinking, is an essential, complementary process to critical thinking. As a practitioner, there are many situations that arise that do not fit with the ideal or that are not predictable. No individual person for whom nurses care ever fits the ‘average’ because each person and situation is unique. In order to solve problems for these unique situations and individuals, the practitioner needs to be able to develop new approaches and solutions so that all parties have their needs met. Miller and Babcock suggest that:

Because creative thinking is so ‘chaotic’ it means that it needs to be evaluated to ensure that any conclusions that are reached are appropriate. In this regard, Ruggiero understands the mind to have two phases:

In the past, critical thinking has often been presented apart from creative thinking. However, in practice, creative and critical thinking go hand-in-hand. Without creative thinking, critical thinking would be dry and mechanical. Without critical thinking, creative thinking would be chaotic and inefficient. As Ruggiero (1998:81) asserts, ‘[t]o study the art of thinking in its most dynamic form [where creative and critical thinking are intertwined] would be difficult at best’. Consequently, in practice, we need to consider them separately. However, although critical thinking and creative thinking are distinct from each other, they should never be separated.

So what are the characteristics that a critical thinker will demonstrate?Jacobs et al (1997) have developed a set of observable skills that indicate the presence of critical thinking. These are grouped into categories, as described below.

Many more examples of various ways of describing the characteristics of critical thinking could be offered. One way of summarising these is to focus on critical thinking as reasoning. The heart of reasoning is the argument. In what follows, the nature of argument will be described, followed by a survey of the ways in which arguments ‘appear’ in nursing. Suggestions will then be offered regarding the way in which the principles of critical thinking might be applied in these areas. By doing so, the way in which this approach synthesises the skills of critical thinking will become obvious.

In colloquial language the word ‘argument’ is often used for a shouting match between two people who are having a disagreement where the participants are very angry, abusive or physically aggressive. There may be shouting, pointing of fingers, threats, crying, name-calling, and so on.

However, in critical thinking, the term ‘argument’ does not apply to these situations. In fact, these situations are the very opposite of critical thinking. In critical thinking, an argument consists of a conclusion and one or more reasons that are intended to support the conclusion. Figure 21.1 shows the relationship between these parts of an argument. Each reason may or may not have evidence that is intended to support the reason or reasons.

For an argument to be sound, three criteria need to be met. First, the reasons need to be acceptable to the person evaluating the argument. Second, the reasons need to be relevant. And, third, the reasons need to provide adequate grounds for accepting the conclusion. Govier (1992) offers a useful way to remember these three criteria, which she calls the conditions of argument. If the first three letters of the word argument (ARG) are taken on their own, each letter stands for one of the conditions of argument. That is:

Govier’s definitions of each of these conditions are also useful: