The word “science” is from Latin “scientia” which was one of several words for “knowledge” in that language. For Aristotle, scientific knowledge was a body of reliable knowledge that can be logically and rationally explained (Source: Wikipedia). This understanding of the term science dominanted for many hundreds of years and was often used interchangeably with the term philosophy. It was only in the 20th century that the natural sciences (physics, chemistry, biology, etc.) came to dominate and the meaning of the term science changed. Science in the English language now usually refers to what used to be known only as natural science. But in many European languages, the word that corresponds to the English science continues to carry the former meaning.
In English one can use the term academic discipline to refer to the old, broader meaning of science. Here is a classification of academic disciplines.
- Natural sciences apply the scientific method to the study of nature. Examples are physics, chemistry, biology, geology, astronomy.
- Social sciences study society. Examples are sociology, anthropology, political science, religious studies, linguistics.
Natural sciences and most of the social sciences are empirical sciences, that is to say that their primary methods rely on data to support or falsify their theories.
- Humanities study the human condition while not relying on data but rather on analytical, critical or speculative methods. Examples are philosophy and literature. Usually visual and performing arts such as music and theatre are included in the humanities although they do not rely on logic or rationality and as such even Aristotle probably wouldn’t have considered them part of science.
- Formal sciences, that is mathematics and related fields, use a priori methods. They are concerned with formal systems based on abstract definitions and rules. As such, the formal sciences themselves are detached from the physical, observable world. However, empirical sciences often rely on mathematics to analyse data gathered from observations.
- Applied sciences use scientific knowledge for practical means. They are very close and sometimes overlap with engineering and R&D.
Depending on their methodology and focus, the fields of history, law, and psychology among others are sometimes assigned to the social sciences, the humanities or even the applied sciences. Computer science also consists of natural science, formal science and applied science.
If we consider all these academic disciplines and exclude the arts, following Aristotle’s understanding of science that is still widespread in continental Europe, what do these sciences then have in common? What makes them scientific? Here is my personal working definition:
‘Science’ (in the general sense) is the systematic and methodical acquisition of knowledge that follows these steps:
- Formulation of a question or problem concerning the world or a general state of affairs (German: “allgemeiner Sachverhalt”).
- Formulation of a theory that is objectively (or intersubjectively) reviewable.
- Publication of the work done in the previous two steps. The publication should document the work as accurately and consistently as possible with the aim of making it rationally or logically comprehensible, reproducible and verifiable (or rather falsifiable, see critical rationalism).
Within the academic disciplines, there has historically been a debate between empiricism and rationalism. The former holding that valid knowledge can only be obtained by sensory experiences while the latter holds that also reasoning is a valid source of knowledge.
I think it would be great if the other sciences, in the old meaning of the word, would reclaim some ground from the empirical, especially natural sciences. Because not everything that matters can be measured (cf. TED Talk by David Brooks).