some valid schemas of first order logic


In this entry, we record some valid schemas of first order logic FO(Σ) based on the signaturePlanetmathPlanetmathPlanetmath Σ:

  1. 1.

    xAyA[y/x] if y does not occur free, but free for x, in A

  2. 2.

    yA[y/x]xA if y does not occur in A

  3. 3.

    xAA if x is not free in A

  4. 4.

    xAA if x is not free in A

  5. 5.

    xyAyxA

  6. 6.

    xyAyxA

  7. 7.

    x(AB)(xAxB)

  8. 8.

    (xAxB)x(AB)

  9. 9.

    x(AB)xAxB

  10. 10.

    x(AB)xAxB

  11. 11.

    x(AB)(xA)B if x is not free in B

  12. 12.

    x(AB)(xA)B if x is not free in B

where A,B are well-formed formulas (wff’s) of FO(Σ).

Title some valid schemas of first order logic
Canonical name SomeValidSchemasOfFirstOrderLogic
Date of creation 2013-03-22 19:32:28
Last modified on 2013-03-22 19:32:28
Owner CWoo (3771)
Last modified by CWoo (3771)
Numerical id 11
Author CWoo (3771)
Entry type Definition
Classification msc 03B10