[SystemSafety] Difference between software reliability and astrology

[Prof. Dr. Peter Bernard Ladkin]

On 2024-08-13 13:17 , Derek M Jones wrote:
>
> It does not work this was for software reliability models because
> of the lack of evidence of what works or does not work.

If you reject the statistical processes that are generally recognised to model software behaviour, 
it is not really surprising that you encounter a "lack of evidence" for anything different. If you 
don't like "2 + 2 = 4" and prefer searching for "2 + 2 = <something other than 4>" it is equally 
unsurprising that you encounter a "lack of evidence" for it.

>
> Arguments are ego and bluster based, and arguing from authority (your
> favorite).

An argument from authority has the following form:

(I)

1. <authority> claims A.
2. Therefore A.

This is different from the following argument:

(II)

1. <authority> claims A, on the basis of the following: <reasoning chain R, of which A is the last 
member>.
2.  <reasoning chain R, of which A is the last member> is correct.
3.  The assumptions used in R hold.
4.  Therefore A.

2, 3, and 4 constitute all the argument anyone needs to conclude A. 1 is not needed, except to 
indicate peripherally that <authority> agrees with you; or maybe that <authority> invented chain R 
and you want to indicate precedence.

You should try not to confuse (I) and (II). Of course, if all you do is speak in and observe 
aphorisms, then you can easily confuse them, because (II) has three distinct steps and you can't 
summarise that in an aphorism.

PBL

Prof. Dr. Peter Bernard Ladkin
Causalis Limited/Causalis IngenieurGmbH, Bielefeld, Germany
Tel: +49 (0)521 3 29 31 00