Unification - artificial intelligence, Computer Engineering

Assignment Help:

Unification - Artificial intelligence:

We have said that the laws of inference for propositional logic detailed in the previous lecture can also be used in first-order logic. However, we have to clear that a little. One important distinction between propositional and first-order logic is that the latter has predicates with expressions as arguments. So, one explanation we have to form is that we may use the inference lawsas long as the predicates and Arguments match up. That's why, not only do we have to check for the right kinds of sentence before we may carry out a law of inference, we also need to check that the arguments do not prohibit the inference.

For instance, let it in our knowledge base, we have the these two statements:

Knows (john) -> hates(john, X)

Knows(john, marry)

and we need to use the Modus Ponens law to infer something latest. In this case, there is no difficulty, and we may infer that, because john hates everybody  he knows, and he knows Mary, then he should hate Mary, i.e., we may infer that hates(john, mary) is right.

However, let it instead that we had these two sentences:

knows(john,X) -> hates(john, X)

knows(jack, mary)

Here, the predicate names have not altered, but the arguments are handling us back from forming any deductive inference. In the first case above, we might allow the variable X to be instantiated to marry during the assumption, and the constant john before and after the assumption also matched without error. However, in the second case, although we might still instantiate X to marry, we could no longer match john and jack, because they are two dissimilar constants. So we cannot deduce anything for john (or anyone else) from the latter two statements.

The problem here arises from our incapability to make the arguments in knows(john, X) and the arguments in knows(jack, marry) match up. When we may make two predicates match up, we say that we have combined them, and we will look at an algorithm for unifying two predicates (if they can be combined) in this section. Remember that unification acts a part in the way Prolog searches for matches to queries.


Related Discussions:- Unification - artificial intelligence

Illustrate the ftp commands, Q. Illustrate the FTP commands? FTP includ...

Q. Illustrate the FTP commands? FTP includes many commands however only few are used to retrieve a file. A user is required to understand the three basic commands to connect to

VLSI implementation of control unit, Q. VLSI Implementation of Control Unit...

Q. VLSI Implementation of Control Unit? A main potential advantage of RISC is VLSI implementation of microprocessor. VLSI Technology has decreased the delays of transfer of inf

Define briefly about extranet, Define briefly about Extranet. Extrane...

Define briefly about Extranet. Extranet: Extranet is Extension of an Intranet which makes the latter available to outside companies or individuals along with or without

Task information displays in search-based tools, Q. Task Information Displa...

Q. Task Information Displays in Search-based tools? Task Information Displays principally give visualization of different locations in parallel program where bottlenecks have o

Describe about analysis, Analysis describes about the logical and statistic...

Analysis describes about the logical and statistical analysis needed for an efficient output. This involves writing of code and performing calculations, but most part of these lang

Assembly Language program, How to get an output: Please enter a number betw...

How to get an output: Please enter a number between 0 and 6 (Enter to stop): 2 The Day of Week is Tuesday Please enter a number between 0 and 6 (Enter to stop): 9 Input Invalid Ple

Is the process before and after the swap are the same, Is the Process befor...

Is the Process before and after the swap are the same? Give reason. Process before swapping is residing in the primary memory in its original form. The regions (text, data and

DBMS, DEFINE FILE ORGANISATION

DEFINE FILE ORGANISATION

Engineering applications, Engineering Applications A few of the enginee...

Engineering Applications A few of the engineering applications are: Airflow circulation over aircraft machinery, Simulations of simulated ecosystems. Airflow c

Cost involved in inter - processor communication, Cost Involved in Inter-Pr...

Cost Involved in Inter-Processor Communication Because data is assigned to too many processors in a parallel computer whilst executing a parallel algorithm processors may be ne

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd