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

Assembly langaauge microprocessor, write alp to perform bcd addition withou...

write alp to perform bcd addition without using procedure

Hard and soft real time systems, Q. Hard and Soft Real Time Systems? ...

Q. Hard and Soft Real Time Systems? Hard Real Time Systems that guarantee critical tasks are completed on time. Soft Real Time Systems that are less restrictive type o

Describe characteristics needed for an e-commerce server, Describe the addi...

Describe the additional characteristics needed for an e-commerce server? E-commerce services need dynamic configuration abilities and seasonal and every day service configurat

When the get cursor command used in interactive lists, When the get cursor ...

When the get cursor command used in interactive lists? If the hidden information is not enough to uniquely recognize the selected line, the command GET CURSOR is used.  The GET

Ellipse follows the perimeter of the window, A) Execute a program where an ...

A) Execute a program where an ellipse follows the perimeter of the window. B)  Execute a program that can draw graphs, possibly following your plan from last week. Have it graph

Design a mod-6 synchronous counter, Design a MOD-6 synchronous counter usin...

Design a MOD-6 synchronous counter using J-K Flip-Flops. Ans: Design of Mod-6 Counter:   To design the Mod-6 synchronous counter, contain six counter states (that is, from

Ending transactions - data phase, Ending transactions: Either side may...

Ending transactions: Either side may request that a burst end after the present data phase. Simple PCI component that do not support multi-word bursts will always request this

Natural interfaces, A breakthrough in the AI intelligence the development ...

A breakthrough in the AI intelligence the development of natural interfaces is a prerequisite to the optimal use of computers by human beings. It incorporates: a. Natural La

Search mechanisms in prolog - artificial intelligence, Search mechanisms in...

Search mechanisms in Prolog We can utilize this simple Prolog program to describe how Prolog searches: president(X) :- first_name(X, georgedubya), second_name(X, bush). p

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