Principles Vs Values

Starting this discussion from the XpMailingList thread, attempting to find principles that allow XP to be tailored...

My view of what is at the core of XP is fast feedback. (I think everyone thinks it's important I just think it is fundamental)

Well, it's one of the values, which might be seen as our way of saying fundamental. But read on ..

... I think the XP principles are focussed on achieving this fast feedback and if it is achieved the process will be robust to details eg. what the simplest thing actually means.

I'm having difficulty as I observe this principle thing, as follows: the values are Communication, Simplicity, Feedback, Courage. We're working with Dave to find "principles".

Jim Coplien and I had a brief discussion at PLOP some years ago on PrinciplesVsValues. We ended up agreeing that principles are forces and values are resultant positions. This means that a principle pushes you somewhere, and a value is what you end up with then.I also concluded for myself that principles are largely personal, or self-selected, or idiosyncratic, or whatever your favorite adjective there is. It means I can't hope for "universal principles".

Applying this to the Dave/Ron discussion above, there were some principles that drove Ward/Kent/Ron to the four Values of XP. I would expect that these principles were things they extracted from observing successful and unsuccessful project instances. You can easily guess what those might have been from looking at the values and the authors and XP. -- AlistairCockburn

I think you have it backward. At least in the way the words are used in XP. Values are "things that we think are good" they represent directions rather than end points. You use values to make an overall assessment of a situation: if the things you value are there then you expect everything to be okay if they aren't they you expect things to be fubar. Prinicpals are more concrete. You use them to make individual decisions. The principles of XP are: RapidFeedback, AssumeSimplicity?, IncrementalChange?, EmbraceChange and QualityWork?. Each of these is prescriptive and is motivated by one or more of the Values. I have observed that XP also has the value of Humanity (it is the primary force behind QualityWork?) although it is never mentioned. But maybe you are saying that we can discover our values by observing the principles that work for us? -- PhilGoodwin

I stand behind my words. Presumably I could add to them, but not at this instant. cheers --Alistair

I am having a hard time following this conversation. Still, I believe that feedback is THE most important value in XP. I really believe it is the most important thing in life ........ We don't know the right thing to do, so we try, and the faster we get corrected (or told we are ok) the faster we find the right track. NissimHadar

I just tried looking these up in the dictionary (what a concept!!)

My dictionary gives me, for the the first definitions: "basic truth", "rule", "policy" and as examples of those, "principles of democracy", "based on principle", "acting on the principle of..." an example of a principle they give is: "every man for himself".

I often look for principles to be phrased as rules: "The theses lead to the thoses", as in, (A) "More frequent delivery of running code means that fewer intermediate promissory notes are required" which also can be stated as a "truth", as in: "I believe that (A)".

Our interest in value doesn't show up until the 4th entry in my dictionary: "a quality considered desirable" the sole example being "traditional values" Thus "a healthy body" would be considered a value, as would "courage", "simplicity", etc.

From my perspective as a CulturalRelativist, I find that principles are freely nominated would-be truths, selected from the range of experience of the person generating them, and are therefore open to refutation (or more likely, argument). In fact, I operate on that principle :-)

Still left over is the question of which precedes which... values to principles or vice versa.I'll pass on that questions. --AlistairCockburn

Alistair, I have seen you refer to yourself as a CulturalRelativist both here and on the XpMailingList. I can guess what you mean, but would you mind explaining what you mean when you say that, and perhaps what implications it has regarding software development? Since this is off-topic for this page, feel free to email me, or if you think others may want to read it as well, answer here or in its own page. Thanks. -- RichardBash

I find that principles are freely nominated would-be truths...and are therefore open to refutation

That sounds like hypothesis to me. If so, I would say that an initial set of principles/hypotheses will generate a theory or set of values. Those set of values can be used to generate new hypotheses which may in turn cause revision of the theory. At any point, any particular hypothesis may be refuted or require revision. This dances around until you get something relatively stable, you call it XP, and the rest is history... If we want to be nitpicky, I suspect that the first iteration tends to start out with concrete principles that generate values. --JasonYip