Chapter 6: Agents that Reason Logically  Chapter 6: Agents that Reason Logically

1. what is a knowledge-based agent?
2. What are syntax and semantics?
3. What is an inference?
4. What is logic?
5. What is a propositional logic? Re: Chapter 6: Agents that Reason Logically

1.) what is a knowledge-based agent? A knowledge-based agent includes a knowledge base and an inference system. A knowledge base is a set of representations of facts of the world. Each individual representation is called a sentence. The sentences are expressed in a knowledge representation language. The agent operates as follows:
• It TELLs the knowledge base what it perceives.
• It ASKs the knowledge base what action it should perform.
• It performs the chosen action.

2.) What are syntax and semantics? Syntax, which defines all possible sequences of symbols that constitute sentences of the language. Examples: Sentences in a book, bit patterns in computer memory. Semantics, which determines the facts in the world to which the sentences refer.
• Each sentence makes a claim about the world.
• An agent is said to believe a sentence about the world.

3.) What is an inference? Inference is the process of drawing a conclusion by applying clues (of logic, statistics etc.) to observations or hypotheses; or by interpolating the next logical step in an intuited pattern. The conclusion drawn is also called an inference.

4.) What is logic? Logic is for constructing proofs, which give us reliable confirmation of the truth of the proven proposition. It's 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.

5.) What is a propositional logic? A propositional calculus or logic (also a sentential calculus) is a formal system in which formulae representing propositions can be formed by combining atomic propositions using logical connectives, and in which a system of formal proof rules allows certain formulæ to be established as "theorems". Propositional logic is a good vehicle to introduce basic properties of logic. It does not provide means to determine the validity (truth or false) of atomic statements. Instead, it allows you to evaluate the validity of compound statements given the validity of its atomic components.

References:
http://www.rbjones.com/rbjpub/logic/log001.htm
http://en.wikipedia.org/wiki/Logic
http://en.wikipedia.org/wiki/Logic#Propositional_logic_.28sentential_logic.29
http://en.wikibooks.org/wiki/Logic_for_Computer_Science/Propositional_Logic Re: Chapter 6: Agents that Reason Logically

1. what is a knowledge-based agent?

For me, I think knowledge-based agent is an intelligent agent which is program to act as an assistance to human task. In other words, it is like having an own initiative when dealing of certain things.

2. What are syntax and semantics?

With regards to syntax and semantics, I always encounter this kind of a question asking what these both mean. When we say syntax, this term refers to the grammatical structure itself while semantic refers to the meaning of the structure. For example, " The bird is crawling". The sentence is grammatically correct but the meaning makes no sense. In other words, syntax and semantics coincide with each other.

http://www.jguru.com/faq/view.jsp?EID=81

3. What is an inference?

The term inference is simply an act of drawing a conclusion by deductive reasoning from given facts . Such example is,

All men are mortal.
Socrates is a man.
Therefore, Socrates is mortal.

Inference is something to do with validity but it does not refer to the truth of premises, but rather to the form of the interference.

http://en.wikipedia.org/wiki/Inferenc

4. What is logic?

I always find logic as mind freaking and critical because it requires correct reasoning. It solely depend on how a person treat the problem and how he/she understands it. In other words, it is used in most intellectual activities but is studied primarily in the disciplines of philosophy, mathematics, semantics and computer science.

http://en.wikipedia.org/wiki/Logic

5. What is a propositional logic?

Propositional logic also known as sentential and statement logic which studies logical operators and connectives that are used to produce complex statement. In addition, it is assumed that every statement is either true or false and not both. There is also a consideration of connectives used to produce statements whose truth-values of the parts, but additional things such as their necessity, possibility or relatedness to one another.

http://www.iep.utm.edu/prop-log/ Re: Chapter 6: Agents that Reason Logically

Knowldge Based Agent

The concept of this agent is a knowledge base or simply KB. Formally, KB is a set of representation of of facts about the word. Usually, these agents have several representations depending on the environment or the level of intelligence that they used it.
To make it detailed about that, this agent is composed of a knowledge base and an interference mechanism which operates by storing sentences about the world in its knowledge base.

Syntax

The syntax of a language describes the possible configurations that can constitute sentences. In computer system/or a programming language, it is a set of commands that represent this system and it is readable to the machine though the computer systems (one of those is the compiler).

Semantics

This determines the facts in the world in which the sentences refer. With these, the group of syntax will give meaning or sense to the commands to be placed in the computer system.

Inference

In Logic, the main concentration is sound reasoning. And that term is called logical inference or deduction. It is a process that implements the entailment relation between sentences. It also the process of deriving new sentences into old ones.

Logic

Based on the previous definition, thisis the formal systematic study of the principles of valid interference and correct reasoning. It also useful for the commitments about what the world is made of and what gives the knowledge base writer more freedom.

Propositional Logic

This commits only the to the existence of the facts that may or may not be the case in the world being represented. It has a simple syntax and semantics that suffices to illustrate the process of interference.
This is known as a very simple logic.

 http://en.wikipedia.org/wiki/Logic Re: Chapter 6: Agents that Reason Logically

1. what is a knowledge-based agent?
-includes a knowledge base and an inference system, is a set of representations of facts of the world. Each individual representation is called sentence. The sentences are expressed in a knowledge representation language.
The agent operates as follows:
1. It TELLs the knowledge base what it perceives.
2. It ASKs the knowledge base what action it should perform.
3. It performs the chosen action.

2. What are syntax and semantics?
syntax - describes the possible configurations that can constitute sentences.
semantics - determines the facts in the world to which the sentences refer. Without semantics, a sentence is just an arrangement of electrons or a collection of marks on a page.

3. What is an inference?
- refers to reasonable conclusions or possible hypotheses drawn from a small sampling of data.

4. What is logic?
- Logic is used for knowledge representation and problem solving, but it can be applied to other problems as well.

5. What is a propositional logic?
- A propositional logic is a formal system in which formulae representing propositions can be formed by combining atomic propositions using logical connectives, and in which a system of formal proof rules allows certain formulæ to be established as "theorems".

http://www.wisegeek.com/in-science-what-is-an-inference.htm
http://en.wikipedia.org/wiki/Logic#Propositional_logic_.28sentential_logic.29 Re: Chapter 6: Agents that Reason Logically

• Knowledge-based agent begins with some knowledge of the world and of its own actions. It uses logical reasoning to maintain a description of the world as new percepts arrive, and to deduce a course of action that will achieve its goals.

• Syntax of a language describes the possible combination that can comprise sentences. Wherein each sentence is implemented by a physical configuration or physical property of some part of the agent. For now, think of this as being a physical pattern of electrons in the computer's memory. Or in other words, syntax defines the grammatical structure of a sentence. Semantics determines the facts in the world to which the sentences refer. Without semantics, a sentence is just an arrangement of electrons or a collection of marks on a page. Or in other words, the meaning of that structure.

• Inference is the process of deriving logical conclusions from premises known or assumed to be true. It is a process that implements the entailment relation between sentences

• Logic is the study of the principles of reasoning, especially of the structure of propositions as distinguished from their content and of method and validity in deductive reasoning.

• Propositional logic is a mathematical model (or algebra) for reasoning about the truth of logical expressions (propositions). Logical expressions can be manipulated according to algebraic laws, allowing us to reason formally (using deductive reasoning) about a set of premises. Resolution is one particularly important technique that can be used to prove a hypothesis from a set of premises. Agents(chap 6)

1. Knowledge-based agent begins with some knowledge of the world and of its own actions. It uses logical reasoning to maintain a description of the world as new percepts arrive, and to deduce a course of action that will achieve its goals.

2. 2.a Semantics- Grammatical rules for assigning meaning to a sentence.
2.b Syntax- Grammatical rules for specifying correct word order and inflectional structure in a sentence.

3. Inference is the process of drawing a conclusion by applying clues (of logic, statistics etc.) to observations or hypotheses; or by interpolating the next logical step in an intuited pattern. The conclusion drawn is also called an inference.

4. Logic i the nonarithmetic operations performed by a computer, such as sorting, comparing, and matching, that involve yes-no decisions.

5. Propositional Logic is a branch of symbolic logic dealing with propositions as units and with their combinations and the connectives that relate them Agents that Reason Logically

Knowledge Based Agent are agents that are dependent on a KB or Knowledge Base to act upon a given situation. It's knowledge base may accumulate as time pass by but I believe it may stagnate as it is likely that the knowledge and the actions it would make would not any more satisfy the users thus it would come to a point that users would not use the Agent.

Syntax, which defines all possible sequences of symbols that constitute sentences of the language. Examples: Sentences in a book, bit patterns in computer memory. Semantics, which determines the facts in the world to which the sentences refer.

Inference is the process of drawing a conclusion by applying clues (of logic, statistics etc.) to observations or hypotheses; or by interpolating the next logical step in an intuited pattern. The conclusion drawn is also called an inference

Logic is the study of the principles of reasoning, especially of the structure of propositions as distinguished from their content and of method and validity in deductive reasoning.

Propositional Logic is a branch of symbolic logic dealing with propositions as units and with their combinations and the connectives that relate them Re: Chapter 6: Agents that Reason Logically 