Casuistry is reasoning used to resolve moral problems by extracting or extending theoretical rules from particular instances and applying these rules to new instances. The term is also commonly used as a pejorative to criticize the use of clever but unsound reasoning, especially in relation to moral questions (see sophistry).
The agreed meaning of "casuistry" is in flux. The term can be used either to describe a presumably acceptable form of reasoning or a form of reasoning that is inherently unsound and deceptive. Most or all philosophical dictionaries list the neutral sense as the first or only definition. On the other hand, the Oxford English Dictionary states that the word "[o]ften (and perhaps originally) applied to a quibbling or evasive way of dealing with difficult cases of duty." Its textual references, except for certain technical usages, are consistently pejorative (eg. "Casuistry destroys by Distinctions and Exceptions, all Morality, and effaces the essential Difference between Right and Wrong").
While a principle-based approach might claim that lying is always morally wrong, the casuist would argue that, depending upon the details of the case, lying might or might not be illegal or unethical. The casuist might conclude that a person is wrong to lie in legal testimony under oath, but might argue that lying actually is the best moral choice if the lie saves a life. (Thomas Sanchez and others thus theorized a doctrine of mental reservation, which developed into its own branch of casuistry.) For the casuist, the circumstances of a case are essential for evaluating the proper response.
Typically, casuistic reasoning begins with a clear-cut paradigmatic case. In legal reasoning, for example, this might be a precedent case, such as premeditated murder. From it, the casuist would ask how closely the given case currently under consideration matches the paradigmatic case. Cases like the paradigmatic case ought to be treated likewise; cases unlike the paradigm ought to be treated differently. Thus, a man is properly charged with premeditated murder if the circumstances surrounding his case closely resemble the exemplary premeditated murder case. The less a given case is like the paradigm, the weaker the justification is for treating that case like the paradigmatic case.
Casuistry is a method of case reasoning especially useful in treating cases that involve moral dilemmas. It is a branch of applied ethics. It is also criticized for the use of inconsistent—or outright specious—application of rule to instance.
Casuistry takes a relentlessly practical approach to morality. Rather than using theories as starting points, casuistry begins with an examination of cases. By drawing parallels between paradigms, or so-called "pure cases", and the case at hand, a casuist tries to determine a moral response appropriate to a particular case.
Casuistry has been described as "theory modest" (Arras, see below). One of the strengths of casuistry is that it does not begin with, nor does it overemphasize, theoretical issues. It does not require practitioners to agree about ethical theories or evaluations before making policy. Instead, they can agree that certain paradigms should be treated in certain ways, and then agree on the similarities, the so-called warrants between a paradigm and the case at hand.
Since most people, and most cultures, substantially agree about most pure ethical situations, casuistry often creates ethical arguments that can persuade people of different ethnic, religious and philosophical beliefs to treat particular cases in the same ways. For this reason, casuistry is widely considered to be the basis for the Englishcommon law and its derivatives.
Casuistry is prone to abuses wherever the analogies between cases are false.
Casuistry dates from Aristotle (384–322 BC), yet the zenith of casuistry was from 1550 to 1650, when the Society of Jesus used case-based reasoning, particularly in administering the Sacrament of Penance (or "confession"). The term casuistry quickly became pejorative with Blaise Pascal's attack on the misuse of casuistry. In Provincial Letters (1656–7) he scolded the Jesuits for using casuistic reasoning in confession to placate wealthy Church donors, while punishing poor penitents. Pascal charged that aristocratic penitents could confess their sins one day, re-commit the sin the next day, generously donate the following day, then return to re-confess their sins and only receive the lightest punishment; Pascal's criticisms darkened casuistry's reputation.
It was not until publication of The Abuse of Casuistry: A History of Moral Reasoning (1988), by Albert Jonsen and Stephen Toulmin, that a revival of casuistry occurred. They argue that the abuse of casuistry is the problem, not casuistry per se (itself an example of casuistic reasoning). Properly used, casuistry is powerful reasoning. Jonsen and Toulmin offer casuistry in dissolving the contradictory tenets of moral absolutism and the common secular moral relativism: "the form of reasoning constitutive of classical casuistry is rhetorical reasoning". Moreover, the ethical philosophies of Utilitarianism (especially preference utilitarianism) and Pragmatism commonly are identified as greatly employing casuistic reasoning.
The progress of casuistry was interrupted toward the middle of the 17th century by the controversy which arose concerning the doctrine of probabilism, which stipulated that one could choose to follow a "probable opinion", that is, supported by a theologian or another, even if it contradicted a more probable opinion or a quotation from one of the Fathers of the Church. The controversy divided Catholic theologians into two camps, Rigorists and Laxists.
Certain kinds of casuistry were criticized by early Protestant theologians, because it was used in order to justify many of the abuses that they sought to reform. It was famously attacked by the Catholic and Jansenist philosopher Pascal, during the formulary controversy against the Jesuits, in his Provincial Letters as the use of rhetorics to justify moral laxity, which became identified by the public with Jesuitism; hence the everyday use of the term to mean complex and sophistic reasoning to justify moral laxity. By the mid-18th century, "casuistry" had become a synonym for specious moral reasoning. However, Puritans were well known for their own development of casuistry.
In 1679 Pope Innocent XI publicly condemned sixty-five of the more radical propositions (stricti mentalis), taken chiefly from the writings of Escobar, Suarez and other casuists as propositiones laxorum moralistarum and forbade anyone to teach them under penalty of excommunication. Despite this papal condemnation, both Catholicism and Protestantism permit the use of ambiguous and equivocal statements in specific circumstances.
G. E. Moore dealt with casuistry in chapter 1.4 of his Principia Ethica, in which he claims that "the defects of casuistry are not defects of principle; no objection can be taken to its aim and object. It has failed only because it is far too difficult a subject to be treated adequately in our present state of knowledge". Furthermore, he asserted that "casuistry is the goal of ethical investigation. It cannot be safely attempted at the beginning of our studies, but only at the end".
Since the 1960s, applied ethics has revived the ideas of casuistry in applying ethical reasoning to particular cases in law, bioethics, and business ethics, so the reputation of casuistry is somewhat rehabilitated.
JesuitPope Francis has criticised "the practice of setting general laws on the basis of exceptional cases" as casuistry.
^170 "Casuistry..destroys, by distinctions and exceptions, all morality, and effaces the essential difference between right and wrong." Henry St. John, Viscount Bolingbroke, Letters on the Spirit of Patriotism 1736 (pub. 1749), quoted in Oxford English Dictionary, 1989 ed.
^Jonsen, Albert R., The Abuse of Casuistry: A History of Moral Reasoning, University of California Press, 1988. ISBN0-52-006063-6 (p. 2).
^Kelly, J.N.D., The Oxford History of the Popes, Oxford University Press, 1986. ISBN0-19-282085-0 (p. 287).