Principia mathematica, by Alfred North Whitehead ... and Bertrand Russell.

232

232 ~~~~MATHEMATICAL LOGIC[PR

[PART I

*24-13.
Demn
*24-14.
Dew?
*24-141.
Dew,
*24-15.
Dern,

FaA.=-.a CA
F. *24-12. *4,73.:): Ia C A. CA. AC Ca.
[*22-41] - a=A:)I-.Prop,
F: (x). wE a * a=V,
F. *24-102. ) F::(). x ca.n (x a) =V.[*20-32] za= V: DF. Prop
F: VCa..V =a
F. *24-11. *4173. -: F: V Ca. a C V. V C a.
[*22-41] Ea =V: DF.Prop
F: (x. x'-,,e a *E a= A
F.- *24-103. ) F:(x).x'-..ea.=E.X(xea)=A.
[*20-32] =-. a=A::)F. Prop
F a =V -..- a = A [*22-83.(*24-02)]
F a i- a =A [*24-103. *22-89]
F a v- a =V [*22-88. *24-102]
F rA = A [*24-12. *22-621]
Fa uA =a [*24-12. *22-62]
above two propositions (*24-23-24) exhibit the algebraical -analogy of

*24-17.
*24-21.
*24-22.
*24-23.
*24-24.
The

A to zero.
*24-26. F. a r% V =a [*22-621.*24,11]
This exhibits, the analogy of V to 1.
*24-27. F-avV=V [*22-62.*24-11]
This exhibits the analogy of V to oc.
*24-3. F: a C/3.Ea-/3= A
Demn.
F *4-53-6.)
F.XE a. X 6e 8 W3 ~ xE a. Xr..JE,8
[*22-35]:e(xe a. xE3)
[*22-33] X6a-8
F.(1). *10-11 271.
F: a C,3. =-. (x)..(x ca -/).
[*24-15] =Ea-/3=A::)F.Prop
The above proposition is very frequently used.

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