证据与法律推理

1. 证据与法律推理 主讲人：熊明辉教授

2. 我的联系方式 • 办公地点 南校区文科三楼逻辑与认知研究所304C室 • 联系电话 办公室：84113340 手机：13678924906 • 电子邮箱 • hssxmh@mail.sysu.edu.cn • xiongminghui@foxmail.com • 即时通号 QQ: 1164157358 飞信：798283253 • 个人主页 • http://logic.sysu.edu.cn/faculty/xiongminghui 共125页

3. 教学纪律 • 作业 • 完成PPT上每讲之后课外作业，通过电子邮件提交，过期补交不予认可。 • 作业提交电子专业用邮箱：legalreasoning09@gmail.com. • 考试 • 本门课程不安排期中考试。 • 期末考试为课程论文，第17周星期三之前提交论文电子版到专用邮箱，并且星期三上课时间提交打印稿，过期提交一律不予认可。 • 期末成绩=平时成绩(40%)+考试成绩(60%)。其中，平时成绩根据课堂表现和课外作业完成情况与质量评定。 期末课程论文题目 （选做一题，论文不少于6000字） 我国当前证据法中存在的问题及其对策 试论法律与逻辑的关系 共125页

4. 目录 • 第1讲 导 论 • 第2讲 法律证据 • 第3讲 法律推理 • 第4讲 法律逻辑 • 第5讲 法律分析 • 第6讲 法律论证 • 第7讲 法律解释 • 第8讲 侦查推理 逻辑都是形式的吗？ 法律推理的方法 眼架方法 法律五段论 共125页

5. 教学计划 共125页

6. 目录 • 第1讲 导 论 • 第2讲 法律证据 • 第3讲 法律推理 • 第4讲 法律逻辑 • 第5讲 法律分析 • 第6讲 法律论证 • 第7讲 法律解释 • 第8讲 侦查推理 逻辑都是形式的吗？ 法律推理的方法 眼架方法 法律五段论 共125页

7. 本讲参考书目 • 熊明辉著，逻辑学导论，复旦大学出版社，2011年。 • 熊明辉著，诉讼论证：诉讼博弈的逻辑分析，中国政法大出版社，2010年。 • 沃尔顿著，梁庆寅、熊明辉等译，法律论证与证据，中国政法大学出版社，2010年。 • http://en.wikipedia.org/wiki/Logic • http://groups.csail.mit.edu/dig/TAMI/inprogress/LegalReasoning.html 共125页

8. 逻辑都是形式的吗？ • Logic (from the Greek λογικήlogikē) is the formal systematic study of the principles of valid inference and correct reasoning. • Logic is used in most intellectual activities, but is studied primarily in the disciplines of philosophy, mathematics, semantics, and computer science. • Logic examines general forms which arguments may take, which forms are valid, and which are fallacies. • In philosophy, the study of logic figures in most major areas: epistemology, ethics, metaphysics. • In mathematics, it is the study of valid inferences within some formal language. • Logic is also studied in argumentation theory. 共125页

9. 逻辑都是形式的吗？ • Logic was studied in several ancient civilizations, including the Indian subcontinent, Persia, Chinaand Greece. Logic was established as a discipline by Aristotle, who gave it a fundamental place in philosophy. The study of logic was part of the classical trivium. • The trivia (singular trivium) are the three lower ArtesLiberales, i.e. grammar, rhetoric and logic. • Logic is often divided into two parts, inductive reasoning and deductive reasoning. 共125页

10. 逻辑都是形式的吗？ • Nature • The concept of logical form is central to logic, it being held that the validity of an argument is determined by its logical form, not by its content. Traditional Aristotelian syllogistic logic and modern symbolic logic are examples of formal logics. • Informal logic is the study of natural languagearguments. The study of fallacies is an especially important branch of informal logic. The dialogues of Platoare good examples of informal logic. 共125页

11. 逻辑都是形式的吗？ • Nature • Formal logic is the study of inference with purely formal content (structure). • An inference possesses a purely formal content if it can be expressed as a particular application of a wholly abstract rule, that is, a rule that is not about any particular thing or property. The works of Aristotle contain the earliest known formal study of logic. • Modern formal logic follows and expands on Aristotle. In many definitions of logic, logical inference and inference with purely formal content are the same. • This does not render the notion of informal logic vacuous, because no formal logic captures all of the nuance of natural language. 共125页

12. 逻辑都是形式的吗？ • Nature • Symbolic logic is the study of symbolic abstractions that capture the formal features of logical inference. Symbolic logic is often divided into two branches: propositional logic and predicate logic. • Mathematical logic is an extension of symbolic logic into other areas, in particular to the study of model theory, proof theory, set theory, and recursion theory. 共125页

13. 逻辑都是形式的吗？ • Logic (from ancient Greekλόγος (logos), meaning reason) is the study of arguments. Its primary task is to set up criteria for distinguishing good from bad arguments. • Arguments express inferences —the processes whereby new assertions are produced from already established ones. As such, of particular concern in logic is the structure of arguments—the formal relations between the newly produced assertions and the previously established ones, where "formal" means that the relations are independent of the assertions themselves. • Just as important is the investigation of validity of inference, including various possible definitions of validity and practical conditions for its determination. • It is thus seen that logic plays an important role in epistemology in that it provides a mechanism for extension of knowledge. 共125页

14. 逻辑都是形式的吗？ • As a byproduct, logic provides prescriptions for reasoning, that is, how people—as well as other intelligent beings, machines, and systems—ought to reason. • However, such prescriptions are not essential to logic itself; rather, they are an application. How people actually reason is usually studied in other fields, including cognitive psychology. 共125页

15. 逻辑都是形式的吗？ • Traditionally, logic is studied as a branch of philosophy. Since the mid-1800s logic has been commonly studied in mathematics, and, even more recently, in computer science. • As a science, logic investigates and classifies the structure of statements and arguments and devises schemata by which these are codified. The scope of logic can therefore be very large, including reasoning about probability and causality. • Also studied in logic are the structure of fallacious arguments and paradoxes. The ancient Greeks divided dialectic into logic and rhetoric. Rhetoric, concerned with persuasive arguments, would currently be seen as contrasted with logic, in some sense; as is dialectic in most of its acquired meanings. 共125页

16. 逻辑都是形式的吗？ • Scope of logic • As it has developed, many distinctions have been introduced into logic. • These distinctions serve to help formalize different forms of logic as a science. Here are some of the more important distinctions. 共125页

17. 逻辑都是形式的吗？ • Deductive and inductive reasoning • Originally, logic consisted only of deductive reasoning which concerns what follows universally from given premises. • However it is important to note that inductive reasoning—the study of deriving a reliable generalization from observations—has sometimes been included in the study of logic. • Correspondingly, we must distinguish between deductive validity and inductive validity. • An inference is deductively valid if and only if there is no possible situation in which all the premises are true and the conclusion false. 共125页

18. 逻辑都是形式的吗？ • Deductive and inductive reasoning • The notion of deductive validity can be rigorously stated for systems of formal logic in terms of the well-understood notions of semantics. • Inductive validity on the other hand requires us to define a reliable generalization of some set of observations. The task of providing this definition may be approached in various ways, some less formal than others; some of these definitions may use mathematical models of probability. • For the most part our discussion of logic deals only with deductive logic. 共125页

19. 逻辑都是形式的吗？ • Formal and informal logic • The study of logic is divided into formal and informal logic. • Formal logic (sometimes called "symbolic logic") attempts to capture the nature of logical truth and inference in formal systems, which consist of a formal language, a set of rules of derivation (often called "rules of inference"), and sometimes a set of axioms. • The formal language consists of a (often small) set of discrete symbols, a syntax, and (often) a semantics, and expressions in this language are often called "formulas". • The rules of derivation and potential axioms then operate with the language to specify a set of theorems, which are formulas that are either axioms or are derivable using the rules of derivation. 共125页

20. 逻辑都是形式的吗？ • Formal and informal logic • In the case of formal logical systems, the theorems are often interpretable as expressing logical truths (tautologies), and in this way can such systems be said to capture at least a part of logical truth and inference. • Formal logic encompasses a wide variety of logical systems. For instance, propositional logic and predicate logic are a kind of formal logic, as well as temporal logic, modal logic, Hoare logic, the calculus of constructions, etc. Higher-order logics are logical systems based on a hierarchy of types. 共125页

21. 逻辑都是形式的吗？ • Informal logic is the study of logic as used in natural language arguments. • Informal logic is complicated by the fact that it may be very hard to tease out the formal logical structure embedded in an argument. • Informal logic is also more difficult because the semantics of natural language assertions is much more complicated than the semantics of formal logical systems, due to the presence of such phenomena as defeasibility. 共125页

22. 逻辑都是形式的吗？ • In judicial opinions, the use of defeasible is commonplace. • There is however disagreement among legal logicians whether defeasible reasoning is central, e.g., in the consideration of open texture, precedent, exceptions, and rationales, or whether it applies only to explicit defeasance clauses. • H.L.A. Hart in The Concept of Law gives two famous examples of defeasibility: "No vehicles in the park" (except during parades); and "Offer, acceptance, and memorandum produce a contract" (except when the contract is illegal, the parties are minors, inebriated, or incapacitated, etc.). 共125页

23. 逻辑都是形式的吗？ • Defeasible reasoning is a kind of reasoning that is based on reasons that are defeasible, as opposed to the indefeasible reasons of deductive logic. • Defeasible reasoning is a particular kind of non-demonstrative reasoning, where the reasoning does not produce a full, complete, or final demonstration of a claim, i.e., where fallibility and corrigibility of a conclusion are acknowledged. • Other kinds of non-demonstrative reasoning are probabilistic reasoning, inductive reasoning, statistical reasoning, abductive reasoning, and paraconsistent reasoning. • Defeasible reasoning is also a kind of ampliative reasoning because its conclusions reach beyond the pure meanings of the premises. 共125页

24. 逻辑都是形式的吗？ 2 Paradigms of logic2.1 Aristotelian logic2.2 Predicate logic2.3 Modal logic2.4 Dialectical logic2.5 Mathematical logic2.6 Philosophical logic2.7 Logic and computation 共125页

25. 逻辑都是形式的吗？ • The motivation for the study of logic in ancient times was clear, as we have described: it is so that we may learn to distinguish good from bad arguments, and so become more effective in argument and oratory, and perhaps also, to become a better person. • This motivation is still alive, although it no longer takes centre stage in the picture of logic; typically dialectical logic will form the heart of a course in critical thinking, a compulsory course at many universities, especially those that follow the American model. 共125页

26. 逻辑都是形式的吗？ 演绎逻辑 deductive logic 形式逻辑 formal logic 归纳逻辑 inductive logic 非形式逻辑 informal logic 共125页

27. 逻辑都是形式的吗？ 我们的结论： 逻辑并不都是形式的。 共125页

28. 逻辑都是形式的吗？ • Logic (from the Greek λογικήlogikē) is the formal systematic study of the principles of valid inference and correct reasoning. • Logic is used in most intellectual activities, but is studied primarily in the disciplines of philosophy, mathematics, semantics, and computer science. • Logic examines general forms which arguments may take, which forms are valid, and which are fallacies. • In philosophy, the study of logic figures in most major areas: epistemology, ethics, metaphysics. • In mathematics, it is the study of valid inferences within some formal language. • Logic is also studied in argumentation theory. 共125页

29. 逻辑都是形式的吗？ • Logic (from ancient Greekλόγος (logos), meaning reason) is the study of arguments. Its primary task is to set up criteria for distinguishing good from bad arguments. Arguments express inferences—the processes whereby new assertions are produced from already established ones. As such, of particular concern in logic is the structure of arguments—the formal relations between the newly produced assertions and the previously established ones, where "formal" means that the relations are independent of the assertions themselves. Just as important is the investigation of validity of inference, including various possible definitions of validity and practical conditions for its determination. It is thus seen that logic plays an important role in epistemology in that it provides a mechanism for extension of knowledge. 共125页

30. 逻辑都是形式的吗？ • Inference • Reasoning • Argument • Argumentation • Proof 共125页

31. 逻辑都是形式的吗？ • Inference • Reasoning • Argument • Argumentation • Proof 共125页

32. 逻辑都是形式的吗？ • Inference is the act or process of deriving logical conclusions from premises known or assumed to be true. The conclusion drawn is also called an inference. The laws of valid inference are studied in the field of logic. • Human inference (i.e. how humans draw conclusions) is traditionally studied within the field of cognitive psychology; artificial intelligence researchers develop automated inference systems to emulate human inference. Statistical inference allows for inference from quantitative data. 共125页

33. 逻辑都是形式的吗？ • Inference • Reasoning • Argument • Argumentation • Proof 共125页

34. 逻辑都是形式的吗？ • The faculty of reason also known as rationality, or the faculty of discursive reason (in opposition to "intuitive reason") is a virtue that governs the exploratory interactions of humans with the universe - such as those employed in our practice of the natural sciences. • It is a mental ability found in human beings and normally considered to be a definitive characteristic of human nature. • It is closely associated with such human activities as language, science, art, mathematics and philosophy. 共125页

35. 逻辑都是形式的吗？ • Reason, like habit or intuition, is a means by which thinking comes from one idea to a related idea. • But more specifically, it is the way rational beings propose and consider explanations concerning cause and effect, true and false, and what is good or bad. • In contrast to reason as an abstract noun, a reason is a consideration which explains or justifies some event, phenomenon or behavior. • The ways in which human beings reason through an argument are the subject of inquiries in the field of logic. 共125页

36. 逻辑都是形式的吗？ • Reason is closely identified with the ability to self-consciously change beliefs, attitudes, traditions, and institutions, and therefore with the capacity for Freedom and self-determination. • Psychologists and cognitive scientists have attempted to study and explain how people reason, e.g. which cognitive and neural processes are engaged, and how cultural factors affect the inferences that people draw. • The field of automated reasoning studies how reasoning may or may not be modeled computationally. • Animal psychology considers the controversial question of whether animals can reason. 共125页

37. 逻辑都是形式的吗？ • Inference • Reasoning • Argument • Argumentation • Proof 共125页

38. 逻辑都是形式的吗？ • An argument in logic is either (a) a set of one or more meaningful declarative sentences in a natural language known as the premises along with another sentence known as the conclusion or (b) a non-empty collection of formulas in a formal language, one of which is designated to be the conclusion . • An argument in a formal language shows the logical form of the natural language arguments obtained by its interpretations. 共125页

39. 逻辑都是形式的吗？ • Logical argument • An argument is an attempt to demonstrate the truth of an assertion called aconclusion, based on the truth of a set of assertions called premises. • The process of demonstration of deductive and inductive reasoning shapes the argument, and presumes some kind of communication, which could be part of a written text, a speech or a conversation. 前提 演绎支持 归纳支持 结论 共125页

40. 逻辑都是形式的吗？ • Inference • Reasoning • Argument • Argumentation • Proof 共125页

41. 逻辑都是形式的吗？ • Argumentation theory, or argumentation, is the interdisciplinary study of how humans should, can, and do reach conclusions through logical reasoning, that is, claims based, soundly or not, on premises. • It includes the arts and sciences of civil debate, dialogue, conversation, and persuasion. • It studies rules of inference, logic, and procedural rules in both artificial and real world settings. • Argumentation includes debate and negotiation which are concerned with reaching mutually acceptable conclusions. • It also encompasses eristic dialog, the branch of social debate in which victory over an opponent is the primary goal. 共125页

42. 逻辑都是形式的吗？ • This art and science is often the means by which people protect their beliefs or self-interests in rational dialogue, in common parlance, and during the process of arguing. • Argumentation is used in law, for example in trials, in preparing an argument to be presented to a court, and in testing the validity of certain kinds of evidence. • Also, argumentation scholars study the post hoc rationalizations by which organizational actors try to justify decisions they have made irrationally. 共125页

43. 逻辑都是形式的吗？ • Key components of argumentation • Understanding and identifying arguments, either explicit or implied, and the goals of the participants in the different types of dialogue. • Identifying the premises from which conclusions are derived • Establishing the "burden of proof" — determining who made the initial claim and is thus responsible for providing evidence why his/her position merits acceptance. 共125页

44. 逻辑都是形式的吗？ • Key components of argumentation • For the one carrying the "burden of proof", the advocate, to marshal evidence for his/her position in order to convince or force the opponent's acceptance. The method by which this is accomplished is producing valid, sound, and cogent arguments, devoid of weaknesses, and not easily attacked. • In a debate, fulfillment of the burden of proof creates a burden of rejoinder. One must try to identify faulty reasoning in the opponent’s argument, to attack the reasons/premises of the argument, to provide counterexamples if possible, to identify any logical fallacies, and to show why a valid conclusion cannot be derived from the reasons provided for his/her argument. 共125页

45. 逻辑都是形式的吗？ • Pragma-dialectics • Scholars at the University of Amsterdam in the Netherlands have pioneered a rigorous modern version of dialectic under the name pragma-dialectics. • The intuitive idea is to formulate clearcut rules that, if followed, will yield rational discussion and sound conclusions. • FransH. van Eemeren, the late Rob Grootendorst, and many of their students have produced a large body of work expounding this idea. 共125页

46. 逻辑都是形式的吗？ • Pragma-dialectics • The dialectical conception of reasonableness is given by ten rules for critical discussion, all being instrumental for achieving a resolution of the difference of opinion. • The theory postulates this as an ideal model, and not something one expects to find as an empirical fact. • The model can however serve as an important heuristic and critical tool for testing how reality approximates this ideal and point to where discourse goes wrong, that is, when the rules are violated. • Any such violation will constitute a fallacy. 共125页

47. 逻辑都是形式的吗？ • Inference • Reasoning • Argument • Argumentation • Proof 共125页

48. 逻辑都是形式的轻吗？ • Proofmay refer to: • Proof (truth), sufficient evidence or argument for the truth of a proposition • Formal proof • Mathematical proof • Proof theory, a branch of mathematical logic that represents proofs as formal mathematical objects • Evidence, information which tends to determine or demonstrate the truth of a proposition • Evidence (law), tested evidence or a legal proof • Alcohol proof, a measure of an alcoholic drink's strength • Artist's proof, a single print taken during the printmaking process • Galley proof, a preliminary version of a publication • Prepress proof, a facsimile of press artwork for job verification • Proof coinage, coins once made as a test, but now specially struck for collectors • Proofreading, reviewing a manuscript or artwork for errors or improvements • Proofing (baking technique), the process by which a yeast-leavened dough rises, also called "proving" 共125页

49. 逻辑都是形式的吗？ http://www.dougwalton.ca/ • We define the word argument in terms of reasoning, and reasoning in terms of inference. • An inference is a set of propositions, one of which is designated a conclusion (end point) and the others are designated premises (start points). • The inference “goes” from the premises to the conclusion. Evidence that an inference exists in a text of discourse is indicated by the so-called indicator words-thus, therefore, so, on this basis, and so on. • Reasoningis a sequence of propositions and, more particularly, is a sequence of inferences linked together such that the conclusion of one inference also functions as premise in the next inference in the chain. 共125页

50. 逻辑都是形式的吗？ • We define the word argument in terms of reasoning, and reasoning in terms of inference. • Then an argument is defined as a sequence of reasoning, a network of propositions in which some propositions, functioning as conclusions, are inferred from others, functioning as premises by means of inferences. 共125页