The origins of law: nature or science?
As a general proposition, laws are too diverse in order to classify them within a single universal definition. What can be certain is that searching for laws is one of the main goals of natural science. The laws of nature ascend from written law made by men. They are presumed precepts of society; dictates of public conscience and formulate a common consensus of morality. A salient question is whether the laws of nature originate naturally from the world or from some supernatural, divine force. Further, whether laws of nature create a package of rules to regulate society or whether they just describe facts and procedure. The answers to these questions depend on what force the laws of nature take, how necessary they are and whether other laws are contingent upon them, whether the laws of nature are distinct and express propositions or rather unintentional generalisations. This introduction shows that there is no overarching philosophical theory of the laws of nature. This is further evinced through an analysis of how difficult it is to relate the various law disciplines to each other (such as physics, chemistry, biology, psychology etc.).
What is the purpose of laws?
Explaining whether laws strictly define or merely suggest the operation of nature is a question usually posed in historical or scientific debates. It was not until the scientific revolution that the idea of scientific law came into being. A balance must be struck between the precedence of divine legislation on one hand, and laws generated from science on the other. Interestingly, though, the creators of scientific law were heavily involved with social, legal and moral order, and thus the laws of nature. God’s will is the origin of such laws, whether they are considered to be laws of nature, descriptions of moral behaviour or laws of how things work. For example, the law of intertia, authored by René Descartes (1596 – 1650) and the order of nature described by Montesquieu (1689 – 1755) were expressly stated to be associated to the purpose of God. However, in as early as the year of 1220, philosophers such as Roger Bacon (1220 – 1292) and Johannes Kepler (1571 – 1630) formulated a type of law that was expressly related to nature, but not to theology. Conceptions of law thus evolved that made descriptions of or gave explanations for nature without making a logical connection to the will of God. From this, the phenomena of prediction, explanation and induction developed.
Following the scientific revolution, laws became something more than mere sources of nature. Laws became regularities, formulated from being deduced or inductively inferred from phenomena and subsequently used in predictions or explanations as required by the new science of mechanics (or the science of ‘how things work’). Laws are generally regarded as imposing rules on the way of life, to regulate the way it is. However, the regularities formulated from the science of mechanics are less considered to prescribe how things work (or should work). Rather, they describe the way things already are. David Hume (1711 – 1776) approved this approach in his empiricist tradition and support for the theory of induction (despite its criticism in 20th century philosophy at the waning of positivism and waxing of both scientific realism and metaphysics).
Scientific theories of laws
Scientific theories have accepted the possibility of predicting every single possible future moment in the world, as well as retrospectively and accurately assessing every single past moment that has taken place. Pierre Simon Laplace (1749 – 1827), who was inspired by Newtonian mechanics, enunciated this theory. Laplace worked with the relationship between matter particles and matter of the universe. Given the weight Laplace attributed to prediction, he theorised laws that have determinative value. These laws can contrast to probabilistic laws, which only attribute probability for phenomena and processes to occur. Such laws do not fall within the category of being the most fundamental laws of reality, however, they may nonetheless be the most realistic type of law. Non-determination can realistically be an aspect of the laws of nature. Without a standard philosophy on what laws of nature are, they can equally be non-determinative as they are determinative of human behaviour.
Causal laws are known as laws that relate to natural processes, whether or not they have determinative value, and whether or not they relate to earlier or later stages (or both). The interaction between causal laws and causation is controversial. This is especially so, in light of analysing the interplay between physical quantities with other kinds of transformation. The concept of symmetry plays an important role in this equation and is an essential force behind understanding the laws of nature. It is not as simple as one plus one equals two, but it is a formula that becomes more simple to discern once the contingency of laws are recognised. This allows one to depict a causal relation between laws that are dependent on other laws – as it requires the necessary law to come first, so that the dependent law can follow, logically and as a matter of causation.
Philosophical theories of laws
Philosophical theories of law are based on ontology, which is the philosophical study of the nature of being, becoming, existence or reality. Empiricists often work within fruitful boundaries of ontology and unfruitful boundaries of metaphysics. Empiricists take a different approach to proponents of necessitation theories. The latter argue that some facts about the world are responsible for the force inherent in the laws of nature. By contrast, the empiricist approach starts with explaining what was in the beginning without using what is in the now to explain what happened in the past. This is the prevailing approach today that takes its form under the regularity theory.
The regularity theory suggests that the laws of nature are universal truths. Further, that laws can be expressed by quantity and predicated by quality. Being a cosmic reality, such as ‘it is impossible to count the number of sand grains on the beach’ and ‘birds fly’, is sufficient for being a law. This theory is an expression of logical positivism: that laws can only be scientifically verified (and thus distinguished from metaphysics). The problem with this theory is that laws can be recognised that are not necessarily cosmic regularities. For example, probabilistic laws depend on the partial truth of probability rather than the full truth of universality. Further, laws that are not universal (such as Newton’s first law: that objects without external force will remain at rest and/or in a straight line) may still be recognised as a genuine law of nature. Thus, the fact that the regularity theory suggests that the laws of nature are universal truths; is a weakness in the theory, because it is equally arguable that the laws of nature are laws that are not constitutive of such truths. A further issue with the regularity theory is that it is hard to distinguish between distinct and express propositions and unintentional generalisations.
The regularity theory and genuine laws of nature found therein are based on the notion of counterfactuals rather than accidentals and counterlegals. For an example of a counterfactual: if a bird had no wings it would not fly. Accordingly, it is a universal truth that birds fly with wings. This shows that counterfactuals are dependent on having a certain account of truth conditions. The truth conditions in the example were that birds have wings and that wings are the only way in which birds can fly. The difficulty with this approach arises in distinguishing between counterfactuals, which are true, and counterlegals, which have already determined what the relevant laws of nature, are. The problems in the regularity theory have opened the gateway to necessitation alternatives.
Necessitation theories draw on the relationship between facts in the world and the laws of nature. The first type of necessitation theory considers laws to be grounded in universal truths. The presence of the relation between two facts (such as the fact that birds need wings in order to fly) presumes a type of necessity between relevant counterfactuals. Cosmic regularity is present in this relationship – but only as a matter of accident rather than necessary intention. The second type of necessitation theory addresses how laws can be created from the causal power of dispositional objects. On this approach, the laws of nature codify types of natural behaviour that have been influenced by intrinsic causal powers.
Laws: more than a mere explanation?
The law is general enough to be described as possessing an explanatory and descriptive power, as well as an imposing and prescriptive power. What must be emphasised, is that it will never be sufficient to merely describe the law as having an explanatory power. The law serves a bigger purpose than merely generalising facts and phenomena. A contingent generalization (in the sense of an explanation), according to David Lewis (1941 – 2001), is only a law of nature if it equates to an axiomatic statement in a deductive system. On this note, explanatory accounts are helpful to the extent that they explain how a certain phenomenon was brought about (as proposed by Carl Hempel (1905 – 1997)). Above all, issues of causation, determinism and symmetry give rise to questions that cannot be answered.
