Browse Definitions :
Definition

logical negation symbol

The logical negation symbol is used in Boolean algebra to indicate that the truth value of the statement that follows is reversed. The symbol resembles a dash with a 'tail' (¬). The arithmetic subtraction symbol (-) or tilde (~) are also used to indicate logical negation.

The simplest use of a negation symbol is with a single sentence. For example, if A represents the statement "The sky is blue," then ¬A represents the statement "The sky is not blue" or "It is not true that the sky is blue."

The negation symbol is often found within, or preceding, complex logical statements. In Boolean algebra, the plus sign (+) represents the logical inclusive OR, and the asterisk (*) represents the logical AND. Rules for use of the logical negation symbol become more complicated when the symbol appears in complex statements. For example, these pairs of statements are not equivalent for all A and for all B:

¬(A + B)
(¬A) + (¬B)

¬(A * B)
(¬A) * (¬B)

However, the following pairs of statements are logically equivalent for all A and for all B:

¬(A + B)
(¬A) * (¬B)

¬(A * B)
(¬A) + (¬B)

Also see Boolean algebra, and the Mathematical Symbols .

This was last updated in September 2005
SearchCompliance
  • ISO 31000 Risk Management

    The ISO 31000 Risk Management framework is an international standard that provides businesses with guidelines and principles for ...

  • pure risk

    Pure risk refers to risks that are beyond human control and result in a loss or no loss with no possibility of financial gain.

  • risk reporting

    Risk reporting is a method of identifying risks tied to or potentially impacting an organization's business processes.

SearchSecurity
  • Twofish

    Twofish is a symmetric-key block cipher with a block size of 128 bits and variable-length key of size 128, 192 or 256 bits.

  • walled garden

    On the internet, a walled garden is an environment that controls the user's access to network-based content and services.

  • potentially unwanted program (PUP)

    A potentially unwanted program (PUP) is a program that may be unwanted, despite the possibility that users consented to download ...

SearchHealthIT
SearchDisasterRecovery
  • What is risk mitigation?

    Risk mitigation is a strategy to prepare for and lessen the effects of threats faced by a business.

  • fault-tolerant

    Fault-tolerant technology is a capability of a computer system, electronic system or network to deliver uninterrupted service, ...

  • synchronous replication

    Synchronous replication is the process of copying data over a storage area network, local area network or wide area network so ...

SearchStorage
  • hard disk drive (HDD)

    A computer hard disk drive (HDD) is a non-volatile data storage device.

  • Remote Direct Memory Access (RDMA)

    Remote Direct Memory Access (RDMA) is a technology that enables two networked computers to exchange data in main memory without ...

  • storage (computer storage)

    Data storage is the collective methods and technologies that capture and retain digital information on electromagnetic, optical ...

Close