Replacement and substitution, Computer Engineering

Assignment Help:

Replacement and substitution:

However, equivalences allow us to change one sentence with another without affecting the meaning, it means we know already that replacing one side of an equivalence into the other will have no effect so whatever on the semantics: but it will still be true for the same models. Just assume there we have a sentence S with a sub expression A that we write like S[A]. But there if we know A≡B so we can be sure the semantics of S is unaffected because we replace A with B, i.e. S[A] ≡S[B]. 

However, there we can also use A ≡B to replace any sub expression of S that is an instance of A. But there point to be remember that an instance of a propositional expression A is a 'copy' of A when some of the propositions of have been consistently replaced by original  sub expressions, e.g. to every P has been replaced by ¬Q. So than we call this replacement a substitution, and a mapping from propositions to expressions. Through applying a substitution U to a sentence S,  we find a new sentence S.U that is an instance of S. There always Ii is easy to show that if there A ≡B so A.U ≡B.U just for any substitution U, that is. an instance of an equivalence is as well an equivalence. Thus, an equivalence A ≡B allows us to change a sentence S[A'] to a logically and fundamentally equivalent one S[B'] but if we have substitution U like that A' = A.U and B' = B.U.


Related Discussions:- Replacement and substitution

Higher order predicate logic, Higher Order Predicate Logic : In the v...

Higher Order Predicate Logic : In the very first order predicate logic, we are only allowed to quantify over objects. If we are considered to allow ourselves to quantify over

3D rotation, Magnify a triangle with vertices A = (0,0), B = (3,3) and C = ...

Magnify a triangle with vertices A = (0,0), B = (3,3) and C = (6,4) to twice its size in such a way that A remains in its original position.

Predicate logic - artificial intelligence, Translate the following sentence...

Translate the following sentences into predicate logic, using Russell's theory of definite descriptions to represent the article the. a. The wizzard of Oz fell. b. Everyone a

What is the use of hypertext links in internet access, What is the use of h...

What is the use of hypertext links in Internet access? Use of Hypertext links in Internet access: From the user’s view point, the Web comprised a vast, worldwide collecti

Working of compact disk - computer architecture, Working of compact disk: ...

Working of compact disk: A CD is built from 1.2 mm thick, approximately all-pure polycarbonate plastic and its weighs is approximately 15-20 grams. From the core outward compo

What is the difference among scrollbar and scrollpane, A Scrollbar is a Co...

A Scrollbar is a Component, but not a Container while Scrollpane is a Container and handles its own events and do its own scrolling.

Identify free memory areas in allocation and de-allocations, Name and expla...

Name and explain the popular techniques to identify free memory areas as a result of allocation and de-allocations in a heap. Two well-liked techniques to identify free memory

Explain about barrier, Q. Explain about Barrier? Barrier: No actual tra...

Q. Explain about Barrier? Barrier: No actual transfer of data takes place in this mode unless all the processors involved in the communication execute a particular block, calle

What is boot manager, An EFI boot manager is also used to select and load t...

An EFI boot manager is also used to select and load the operating system, removing the require for a dedicated boot loader mechanism

Define speculative execution, Define speculative execution. Speculative...

Define speculative execution. Speculative execution means that instructions are implemented before the processor is particular that they are in the correct execution sequence.

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