The phrase “nature of science” (NOS) may refer to the epistemology of science or the principles and beliefs inherent to the development of scientific knowledge (Lederman, 1992). However, there is disagreement among the philosophers of science, historians of science, sociologists of science, scientists and science educators about a specific conception of NOS (Abd-El-Khalick & Lederman, 2000a, 2000b). We also acknowledge this lack of agreement, and therefore we will use the phrase ‘NOS’ instead of ‘the NOS’ throughout this paper after Lederman and his colleagues (Abd-El-Khalick & Lederman, 2000a, 2000b).

Lederman and his colleagues (Abd-El-Khalick & Lederman, 2000a, 2000b). After synthesising the major NOS literature (Lederman, 2004; McComas & Olson, 1998; Osborne, Collins, Ratcliffe, Millar, & Duschl, 2003), three NOS aspects are considered in this research: (a) nature of scientific knowledge, (b) nature of scientific inquiry and (c) nature of scientific enterprise, which build the conceptual framework and is discussed below.

Nature of scientific knowledge

Tentative

Even though scientific knowledge is durable, it is never absolute or certain (Lederman, 2004; Osborne, et al., 2003). When new evidence is found against existing knowledge, as a result of advancement of technology or old evidence is reinterpreted in the light of new advanced theory, existing knowledge can be altered (Lederman, 2004). Further, uncertainty of scientific knowledge is observed because it is inferential, subjective, creative and culturally embedded in nature.

Inferential

Although scientific knowledge is “derived from, and/or consistent with observations of natural phenomena” (Abd-El-Khalick, Waters, & Le, 2008, p. 838), it is also inferential in nature. “Observations are descriptive statements about natural phenomena that are ‘directly’ accessible to the senses (or extensions of the senses)” (Lederman, 2004, p. 304). For example, if we release an object above ground level, we can observe its tendency to fall and hit the ground. On the other hand, the object tends to fall to the ground due to the gravity, which is not accessible to our senses and “can only be accessed and/or measured through its manifestations of effects” (Lederman, 2004, p. 305, emphasis in original). This logical conclusion of the observation is called an inference.

Theory-driven and subjective

Scientist’s’ theoretical knowledge, training, experience, commitments, religious or other beliefs, political convictions, sex and ethnic origin can form a mind-set that affects scientific investigations (Lederman, 2004). Different scientists holding different values engage themselves in different forms of scientific investigations (Allchin, 1999). Also, these values influence what they observe (and do not observe) and how they interpret these observations. In other words, these observations help find answers to some questions, which are derived from within certain theoretical perspectives.

Scientific knowledge involves human inference, imagination, and creativity

Despite having an empirical basis of scientific knowledge, it involves scientist’s imagination and creativity (Lederman, 2004). For example, the concepts of atoms, black holes, force fields and species are not faithful copies of reality, rather they are functional theoretical models as a result of creatively integrating NOS and its inferential nature (Abd-El-Khalick, et al., 2008).

Nature and function of theories and laws

Scientific laws are “statements or descriptions of the relationships between observable phenomena”, scientific theories, in contrast are “inferred explanations for observable phenomena” (Lederman, 2004, p. 305). A theory is much more complex and dynamic as it presents the inferred explanations, and it often includes a law(s). For example, in Einstein's theory of relativity, gravity plays a crucial role. In this theory, the basic law of gravity is intact, and the theory expands it to include various and complex situations involving space and time. It is noteworthy that theories and laws are supported by empirical data, are regarded as different kinds of knowledge and one does not become the other (Abd-El-Khalick, et al., 2008). However, it is often believed that after being empirically tested a hypothesis becomes a theory (Haidar, 1999), and “laws-are-mature-theories-fable” (Bell, Lederman, & Abd-El-Khalick, 2000).

Nature of scientific inquiry

Myth of “The Scientific Method”

It is often perceived that there is a recipe-like stepwise procedure in all scientific investigations. However there is no single “scientific method” that would guarantee the development of scientific knowledge (Abd-El-Khalick & Lederman, 2000b; Abd-El-Khalick, et al., 2008; Bell & Lederman, 2003; Lederman, 2004; McComas, et al., 1998). Also, there is no single sequence of practical, conceptual, or logical activities that will accurately lead to valid claims in developing scientific knowledge (Abd-El-Khalick, et al., 2008).

Myth of “The Experimentation”

This myth of NOS refers to the idea that only experimental research characterises scientific inquiry. However, scientific inquiry may take other forms, such as descriptive and correlational (Lederman, 2004). Scientific questions guide the approach employed in getting answers to the questions and the approaches that vary widely within and across scientific disciplines.

Nature of scientific enterprise

Social and cultural embeddedness of science

Science is a human enterprise embedded and practiced in society (Abd-El-Khalick, et al., 2008); therefore, science affects and is affected by different cultural elements, such as social values, power structures, politics, socio-economic factors, philosophy and religion (Lederman & Lederman, 2004). Influence of these factors can be observed by the issue of public funding for scientific research.

Interaction between science and technology

Science and technology have different roles in society. Is important to understand the interaction and have an understanding of the distinctions between science and technology (Buaraphan & Sung-Ong, 2009). However, there are often misconceptions among teachers in this regard, such as “technology is the applied science” (Tairab, 2001).

Cooperation and collaboration in science

Scientific work is a collaborative and collective activity (Lederman, 2004; Osborne, et al., 2003). Although individuals may make significant contributions, scientific work is often carried out in groups. New knowledge claims are generally shared and must go through a double-blind peer review process to be accepted by the scientific community.