Thought and LanguageChapter 8

Peking University

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ELIZA

1960s, MIT A Conversationalist: Demonstrating that it r

ecognizes works and know what rules to use to maintain a dialogue.

What distinguishes ELIZA from human?• Relation between thought and language?• In what ways peoples get to learn language?

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Thought

Thinking, means representing things mentally and operating on these representations.

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Outline

Units of Thought: Images, Concepts, and Propositions

Reasoning, Problem Solving, and Decision Making

Language

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1. Units of Thought: Images, Concepts, and Propositions

Mental Images & Mental Models

Concepts and Categories

Propositions

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1.1 Mental Images and Mental Models

Mental ImageA visual representation of a stimulus.

Mental ModelsRepresentations of systems that enable people to

describe, explain, and predict the way things work.

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1.2 Concepts and Categories

Concepts• Mental representation of a class of objects,

ideas, or events that share common properties.

Categorization• The process of grouping objects considered

equivalent and excluding those that are not.

Visualized & more than visual image(car) Well-defined & Fuzzy Concepts(good)

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动物

脊椎动物 无脊椎动物

鸟类 哺乳类 爬行类

鸟 家禽

肺来呼吸有翼飞行卵生温血

不会飞肺、温血卵生

红嘴鸥

海鸟，红嘴，等。

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Concepts and its Organization

Set Theory• Set of Defining(core) Features

Feature Integration Model Prototypes 原型 Bird----robin & penguin

概念与归类

狗

样例定义特征

德国牧羊犬

猎狗

长毛卷耳狗

玩具狮子狗

四足、有尾动物

吠声、气喘、淌口水

通常受驯养、友好

能捉跳蚤

水果样例的典型性橘子 1 1.07

苹果 2 1.08

香蕉 3 1.15

桃子 4 1.17

杏子 6.5 1.36

葡萄 9 1.38

西瓜 23 2.39

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概念的形成 Hypothesis-testing Theory

• 整体策略• 部分策略

• 同时性扫描• 连续性扫描• 保守性聚焦• 博弈性聚焦

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1.3 Propositions

The smallest units of meaning that can stand alone as an assertion and be judged true or false.

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2. Reasoning, Problem Solving, and Decision Making Reasoning Problem Solving Decision Making

Factors That Interfere with Rational Thinking Parallel Distributed Processing Using Computers to Simulate Thought A Different Perspective: psychodynamic/behavioral vie

w

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2.1 Reasoning Reasoning

• the process by which people generate and evaluate logical arguments

Inductive Reasoning----observation• reasoning from specific observations to

generate propositions that are probably true.

Deductive Reasoning----idea• Drawing conclusions from assumptions or

premises.

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三段论 (Syllogism)

All A(s) are B C is an A C is a B

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三段论推理 未婚者都不戴结婚戒指。 小李未戴结婚戒指。 所以，小李未婚。

卡片一面是数字，一面是字母。 如果卡片一面是字母 A，另一面就是数字 3。 要验证第二个命题，必须翻什么卡片？

未婚者都不戴结婚戒指。 小李未戴结婚戒指。 所以，小李未婚。

卡片一面是数字，一面是字母。 如果卡片一面是字母 A，另一面就是数字 3。 要验证第二个命题，必须翻什么卡片？

A B 3 2

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2.2 Problem Solving

The process of transforming one situation into another that meets a goal.

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2.2.1 The Problem-solving Process

The problem space No problem

InitialState

OperatorsGoalState

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2.2.2 Three Components

Initial state• Existing of problem

Operators• mental and behavioral processes aimed at

transforming the initial state until it eventually approximates the goal state.

Goal state• Problem is solved

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2.2.3 Steps in Problem Solving Holland et al.(1986): four-step process

• Differences between the two states

• Identify and select possible operators

• Apply the operators (Subgoals)

• Continue using operators until differences are eliminated

Well or Ill-defined problem• Science/ Social life(信息和标准 )

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Problem-Solving Strategies

Algorithms• Systematic problem-solving procedures that ine

vitably produce a solution.

Heuristics• Cognitive shortcuts or Rules of Thumb• Hypothesis testing

• Experience/ Expectation/ Motivation/ Personality

• 如何解决：半夜时分隔壁宿舍太闹 /过得不开心

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2.3 Decision Making Decision making

• The process by which an individual weighs the pros and cons of different alternatives in order to make a choice.

Information-processing models• Utility / Probability

Utility Value Weighted Utility Value Expected Utility

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教授 工商界 公务员属性 重要性

效用 加权效用 效用 加权效用 效用 加权效用

高收入 5 5 25 10 50 7 35

有挑战性 4 10 40 9 36 6 24

有发展机会 3 8 24 8 24 8 24

有住房 2 8 16 2 4 10 20

工作环境 1 10 10 6 6 9 9115 120 112

求职成功率 .10 .90 .50

期望效用 11.50 108 56.0

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Risk Strategies (nonstatistical risk estimate)

Which is your choice?• 85% chance to win $100• Sure gain of $80

Which is your choice?• 85% chance to lose $100• Sure loss of $80

Risk-averse/Risk-seeking strategy Optimistic bias(when estimate own risks)

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2.4 Factors That Interfere with Rational Thinking Representativeness & Availability Heuristic

• Deciding whether an object or incident belongs in a particular class.

• Judging the likelihood of something happening on the basis of its availability in memory.

Confirmation Bias• 2,4,6,

Mental Set Functional Fixedness

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2.5 Parallel Distributed Processing Ruelhart et al., 1986:

PDP model of cognition

Two propositions of PDP model• Parallel

• Letter-recognition/ word-recognition

• Distributed

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2.6 Using Computers to Stimulate Thought Artificial Intelligence

• GPS, General Problem Solver• ELIZA• Expert Systems

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2.7 A Different Perspective: Psychodynamic and Behavioral View of Decision Making

Rational decision maker of information-processing theory.

Decisions involve motivation and emotion, which can be too many and irrational and not be represented in conscious awareness.• Syllogism about Chairman Mao• Wilson & Schooler(1991): 草莓酱• Wilson et al.(1993)：艺术画

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Assignment No.4

人类思维过程容易出现失误。为什么？请展开思路，从多个角度加以说明。

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3. Language

The system of symbols, sounds, meanings, and rules for their combination that constitutes the primary mode of communication among humans.

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Main topics on language

Language and Thought Transforming Sounds and Symbols into

Meaning From Babbling to Bantering Nonverbal Communication Is Language Distinct to Humans?

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3.1 Language and Thought

Hununoo (Philippines): 92 names for rice Gender/time phrase in English B. Whorf (1956):Whorfian Hypothesis

Language shapes thought Thought shapes language

• Rosch(1973): Dani people for color(only two)• The United States/These United States

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3.2 Transforming Sounds and Symbols into Meaning Elements of Language

phoneme, morpheme, sentence(phrase), grammar

Slips of the Tongue: Misplacing the Elements of Language(PDP)

Surface and Deep Structure Transformational Grammar

• LAD, Language Acquisition Device

Context and Meaning

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3.3 From Babbling to Bantering

Babbling, One word, Two word,

Telegraphic Speech

Influences on Language Development• genetic predisposition(Eimas, 1985)• environmental influence

• Reinforcement(强化不到位、类似规律、造句 )

Critical Period for Language Development?

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3.4 Nonverbal Communication

Intonation (tone of voice)

Body language *

Gestures

Physical distance

Auditory signals(nonverbal vocalizations)

Facial expressions

Touch or smell

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Is Language Distinct to Humans?

Premack(1972):• A chimpanzee, Sarah, learned a vocabulary of 1

30 plastic symbols.

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4. Some Concluding Thoughts