Showing posts with label apparent variable. Show all posts
Showing posts with label apparent variable. Show all posts

Friday, September 14, 2012

12. Propositions connecting real and apparent variables

Harold R. (Hal) Foster’s Prince Valiant
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Propositions connecting real and apparent variables

 The most important propositions connecting real and apparent variables are the following:

(1) " When a propositional function can be asserted, so can the proposition that all values of the function are true." Stated more briefly, if less exactly, "what holds of any, however chosen, holds of all." This translates itself into the rule that when a real variable occurs in an assertion, we may turn it into an apparent variable by putting the letter representing it in brackets immediately after the assertion-sign.

(2) " What holds of all, holds of any," i.e.

: (x). φx . É . φy.

This states " if φx is always true, then φy is true."

(3) " If φy is true, then φx is sometimes true," i.e.

: φy . É . ($x). φx.

An asserted proposition of the form "($x) . φx" expresses an "existence theorem," namely " there exists an x for which φx is true." The above proposition gives what is in practice the only way of proving existence-theorems: we always have to find some particular y for which φy holds, and thence to infer "($x). φx." If we were to assume what is called the multiplicative axiom, or the equivalent axiom enunciated by Zermelo, that would, in an important class of cases, give an existence-theorem where no particular instance of its truth can be found.

In virtue of " : (x). φx . É. φy" and ": φy . É . ( x). φx," we have

": (x) . φx . É . ($x). φx," i.e. "what is always true is sometimes true. "This would not be the case if nothing existed; thus our assumptions contain the assumption that there is something. This is involved in the principle that what holds of all, holds of any; for this would not be true if there were no " any."

(4)"If φx is always true, and yx is always true, then 'φx . yx' is always true,"' i.e.

:. (x). φx : (x). yx: É (x) . φx . yx.

(This requires that φ and y should be functions which take arguments of the same type. We shall explain this requirement at a later stage.) The converse also holds; i.e. we have

:. (x). φx . yx . É : (x). φx : (x). yx.

It is to some extent optional which of the propositions connecting real and apparent variables are taken as primitive propositions. The primitive propositions assumed, on this subject, in the body of the work (*9), are the following:

(1) : φx . É . ($z) . φz

(2) : φx v φy . É . ($z) . φz,

i.e. if either φx is true, or φy is true, then ($z) . φz is true. (On the necessity for this primitive proposition, see remarks on *9'11 in the body of the work.)

(3) If we can assert φy, where y is a real variable, then we can assert    (x) . φx; i.e. what holds of any, however chosen, holds of all.

Script: Bob Haney  Pencils and Inks: Bernard Baily. ™ © Respective copyright/trademark holders.

In tribal Indian cultures, before European contact, great general continuity of experience and understanding existed of each individual’s place in the world they inhabited.  Certainly this was true within the tribe, and largely between tribes within a given region. The region containing the range of a tribe held great importance for its relation to the identity of every individual. It was understood by all, that the resources of any region were finite, and to be husbanded so that all could share as needed, not just for the family or tribe, but for the resources themselves. For all plants, animals, reptiles, fish and even minerals were living beings with spirits to themselves that were equally sacred as the lives of human beings.
There is evidence that these shared values and perceptions were virtually universal across the continent, allowing of course, for regional and tribal variations. This simplicity and homogenous set of experiences, beliefs and understandings allowed the Indian people to live an existence that includes what I have termed 4D thought, that is, a broad shared set of knowledge that allowed everyone to know the world they lived in and to clearly see how they could fit into it. Language was useful of course, but it was not called upon to convey commercial or technical complexities, rhetoric beyond story, or separation of classes.
The evolution of metaphysical principals, such as those examined in this blog, are valiant attempts to bring order the dissipated perceptions of European language based thought predicated by language in practically every aspect of life. As we contiue, this will become quite apparent I hope.
Script: ?  Pencils: Dick Beck  Inks: Don Perlin ?  © Respective copyright holders.
hanBLOGlaka
Logical Philosophy In American Indian
thought and Perception
Harold R. (Hal) Foster’s Prince Valiant
© Respective copyright/trademark holders.

Monday, September 10, 2012

9. Apparently Variable

Harold R. (Hal) Foster’s Prince Valiant
© Respective copyright/trademark holders.

Apparent variables

The symbols “(x) . φx” denotes a definitive proposition, and there is no distinction between “(x) . φx ” and “(y) . φy” when they occur in the same context. Thus “x” in “(x) . φx” is not an ambiguous constituent in any expression in which “(x) . φx ” occurs; and such an expression does not cease to convey a determinant meaning by reason of the ambiguity if the x in “φx ”.

The range of x in “(x) . φx ” or “($x) . φx” extends over the complete field of the values of x for which “φx” has meaning, and accordingly the meaning of  “(x) . φx ” or “($x) . φx” involves the supposition that such a field is determinant. The x which occurs in “(x) . φx ” or “($x) . φx” is called an “apparent variable” (after Peano). It follows from the meaning of “($x) . φx” that the x in that expression is also an apparent variable. A proposition in which x occurs as an apparent variable is not a function of x. Thus e.g. “(x) . x=x” will mean “everything is equal to itself.” This is an absolute content, not a function of a variable x. This is why the x is called an apparent variable in such cases.

As established in the second edition, there is no need of the distinction between real and apparent variables, nor of the primitive idea “assertion of a propositional function.” On all occasions ahead where, in Principia Mathematica, our authors have an asserted proposition of the form “├ . fx” or “├ . fp” this is to be taken as meaning “ (x) . φx”; but in “ ($x) . φx “ it is necessary to indicate explicitly the fact that “some” x (not “all” x’s) is involved.


 

Script: Gardner F. Fox  Pencil and Inks: Sheldon Moldoff (signed
)Cliff Cornwall™ © Respective copyright/trademark holders.
The text I am working from thus far is the abridged Principia Mathematica to *56, and this edition is drawn from the first edition. There are a number of revisions in the second edition, which were suggested by various readers in the years between editions. As the authors predicted this, and any metaphysical system is and must be in in flux to be useful to its purpose. Even though it became apparent that the distinction between real and apparent variables is not necessary within the system of propositions described ahead, it is nonetheless useful to understand the distinction. Even though the difference is semantic, it is still real, and a detail that may be useful in some not yet anticipated capacity.  
Script: R. D. Blackmore (original author); Ruth A. Roche (adaptation)
Pencils and Inks: Matt Baker © Respective copyright/trademark holders.
 
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Logical Philosophy In American Indian thought and Perception

Harold R. (Hal) Foster’s Prince Valiant
© Respective copyright/trademark holders.