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From: Rowland McDonnell on 21 Jun 2010 18:59 Woody <usenet(a)alienrat.co.uk> wrote: > Ian McCall <ian(a)eruvia.org> wrote: > > > We being the general marketplace, not particular individuals within > > it. Transputers never really caught on in a big way, and all was said > > to be down to optimising compilers and languages for multithreading > > and getting developers to understand it properly. > > I so wanted the atari transputer workstation. I loved the idea of occam > and it seemed such a logical design for the future of computing. Of > course viewing it from a software point of view rather than a world view > didn't help. Was too young to realise (actually care) that the world > didn't want flashy computers, they wanted to write rubbishy powerpoints > instead. [snip] Actually, the world wants useful computers, but has been brainwashed and conned into thinking that by wasting their time producing mind-numbing PowerPoint presentations they are somehow `leveraging modern technology to the optimum extent' instead of just wasting time in ever more expensive and elaborate and sterile ways. Rowland. -- Remove the animal for email address: rowland.mcdonnell(a)dog.physics.org Sorry - the spam got to me http://www.mag-uk.org http://www.bmf.co.uk UK biker? Join MAG and the BMF and stop the Eurocrats banning biking
From: Woody on 21 Jun 2010 19:45 Rowland McDonnell <real-address-in-sig(a)flur.bltigibbet.invalid> wrote: > Woody <usenet(a)alienrat.co.uk> wrote: > >> Ian McCall <ian(a)eruvia.org> wrote: >> >>> We being the general marketplace, not particular individuals within >>> it. Transputers never really caught on in a big way, and all was > > > said >>> to be down to optimising compilers and languages for multithreading >>> and getting developers to understand it properly. >> >> I so wanted the atari transputer workstation. I loved the idea of > > occam >> and it seemed such a logical design for the future of computing. Of >> course viewing it from a software point of view rather than a world > > view >> didn't help. Was too young to realise (actually care) that the world >> didn't want flashy computers, they wanted to write rubbishy > > powerpoints >> instead. > > [snip] > > Actually, the world wants useful computers, but has been brainwashed > and > conned into thinking that by wasting their time producing mind-numbing > PowerPoint presentations they are somehow `leveraging modern > technology > to the optimum extent' instead of just wasting time in ever more > expensive and elaborate and sterile ways. Seems so: <http://www.nytimes.com/2010/04/27/world/27powerpoint.html> -- Woody
From: Rowland McDonnell on 21 Jun 2010 20:59 Woody <usenet(a)alienrat.co.uk> wrote: > Rowland McDonnell <real-address-in-sig(a)flur.bltigibbet.invalid> wrote: [snip] > > Actually, the world wants useful computers, but has been brainwashed > > and conned into thinking that by wasting their time producing > > mind-numbing PowerPoint presentations they are somehow `leveraging > > modern technology to the optimum extent' instead of just wasting time in > > ever more expensive and elaborate and sterile ways. > > Seems so: <http://www.nytimes.com/2010/04/27/world/27powerpoint.html> "`PowerPoint makes us stupid,' Gen. James N. Mattis of the Marine Corps, the Joint Forces commander, said this month at a military conference in North Carolina."[1] I've met similarly-toned British army comments on the problems of PowerPoint, too. Thing is, that's what a lot of people have been pointing out for a lot of years. PowerPoint is a major threat to profitability in your organization - should be hammered in to the heads of all commercial managers everywhere. Do Not Use PowerPoint. End of. I never have done - never felt that it'd help at all. Rowland. [1] He also said: "Some problems in the world are not bullet-izable." - which is a /great/ quote from an army general, even if you know that he means bullet-point lists... -- Remove the animal for email address: rowland.mcdonnell(a)dog.physics.org Sorry - the spam got to me http://www.mag-uk.org http://www.bmf.co.uk UK biker? Join MAG and the BMF and stop the Eurocrats banning biking
From: Richard Tobin on 21 Jun 2010 21:30 In article <1jkgkyj.1ow92o8le1ot2N%real-address-in-sig(a)flur.bltigibbet.invalid>, Rowland McDonnell <real-address-in-sig(a)flur.bltigibbet.invalid> wrote: >Ah - your wording `keep applying parent' told me that `parent' is an >operator for your purposes at this point. I know `parent' as a noun, >not an operator. > >I'm still not sure how you get from: > >`The relation "ancestor" is what you get if you keep applying "parent".' > >to: > >`Your ancestors are the people you get to by taking your parents, their >parents, their parents, ...' I could have been more explicit and called the relations "is-a-parent-of" and "is-an-ancestor-of". I was just abbreviating (a habit of both mathematicians and computer programmers). There's nothing complicated lurking there. >The set of elements that is my ancestors contains only those who are my >parents and the parents of those already identified as being in the set. > >I think that's a nice way of specifying the contents of the set in >question - what do you reckon? It's certainly clear for everyday purposes. It's a procedural definition in that it tells you how to construct the set, and you might feel uncomfortable with that in the case where the set was infinite (or there again you might not). >> The rigorous >> definition of transitive closure would be declarative, rather than >> procedural. >I don't see why that has to be the case, I really don't - one can >unambigiously define plenty of things using a procedural definition. In part it's probably that mathematics has a widely-used notation for declarative definitions, but not for procedural ones. But the boundary isn't clear: you can write declarative definitions that reflect the procedure quite closely. We could say: Given a relation R (e.g. the is-a-parent-of relation), define R2 such that C R2 A iff C R B and B R A (R2 is the is-a-grandparent-of relation). In general, define Rn such that X Rn Z iff X R Y and Y R(n-1) X (Rn is the is-an-nth-generation-back-ancestor-of relation). Then define R' to be the union of R and all the Rn (your ancestors are your parents, your grandparents, your great-grandparents, your great-great-grandparents, ...). >> As I've probably remarked before, "The Origin of Consciousness in >> the Breakdown of the Bicameral Mind" is good on metaphors, even if >> you don't accept its main thesis. >Since my first big problem with that book is its apparent tacit >acceptance of real meaning belonging to the word `consciousness' A large portion of the book is devoted to discussing what, if anything, consciousness is. >Another point is that I'm generally not keen on metaphors for anything >much except humour or illustrating things about people to people >directly in the real-life face-to-face happening-now conversational >world. If I can say this without causing offence, I think it's quite likely that certain kinds of mental illness might make it harder to deal with metaphors. The thesis of the book is that metaphors are central to modern consciousness, and draws parallels between schizophrenia and the conjectured organisation of the mind before modern consciousness developed. Whether any of that is true is still a matter of debate. >3) It's called the closure because you go on until you don't get any >new elements - the resulting set is closed. > >That one, I'm still mildly baffled about. Can you expand? A set is called "closed" under an operation if applying the operation to an element of the set always gives you an element of the set. The set of you and your parents is not closed under the is-a-parent-of relation, because your parents' parents are not in it. The set of you and your ancestors *is* closed under that relation. (I realise I'm conflating the closure of the set under the relation, i.e. you and all your ancestors, with the closure of the relation, i.e. the is-an-ancestor-of relation.) >`In psychology, bicameralism is a hypothesis which argues that the human >brain once assumed a state known as a bicameral mind in which cognitive >functions are divided between one part of the brain which appears to be >"speaking", and a second part which listens and obeys.' >- it's a psychological hypothesis from a professional psychologist. >Which means it's almost certainly total bollocks. Quite possible, but it's really rather interesting bollocks. -- Richard
From: Rowland McDonnell on 22 Jun 2010 00:16
Richard Tobin <richard(a)cogsci.ed.ac.uk> wrote: > Rowland McDonnell <real-address-in-sig(a)flur.bltigibbet.invalid> wrote: > > >Ah - your wording `keep applying parent' told me that `parent' is an > >operator for your purposes at this point. I know `parent' as a noun, > >not an operator. > > > >I'm still not sure how you get from: > > > >`The relation "ancestor" is what you get if you keep applying "parent".' > > > >to: > > > >`Your ancestors are the people you get to by taking your parents, their > >parents, their parents, ...' > > I could have been more explicit and called the relations "is-a-parent-of" > and "is-an-ancestor-of". I was just abbreviating (a habit of > both mathematicians and computer programmers). It's a habit of a lot of people. It's a very bad habit to get into if you're explaining something in heavy technicalese and abbreviate something to the extent that the learner can't figure out its meaning. I was a teacher - I learnt to avoid doing that... > There's nothing > complicated lurking there. <rolls eyes> So? It's just logic and operators and sets, of course it's not complicated; but what it is, is bloody obscure - when you don't explain it clearly. So: we've got this relation, not operator, `is a parent of'. Okay. So: The relation "ancestor" is what you get if you keep applying `is a parent of' But `is a parent of' identifies you as an ancestor, so why do you say `keep applying'? > >The set of elements that is my ancestors contains only those who are my > >parents and the parents of those already identified as being in the set. > > > >I think that's a nice way of specifying the contents of the set in > >question - what do you reckon? > > It's certainly clear for everyday purposes. I think it's precise enough for any purposes - is it? > It's a procedural > definition in that it tells you how to construct the set, and you > might feel uncomfortable with that in the case where the set was > infinite (or there again you might not). The set specified is a finite set; but aside from that: why would anyone feel uncomfortable about defining an infinite set that way? > >> The rigorous > >> definition of transitive closure would be declarative, rather than > >> procedural. > > >I don't see why that has to be the case, I really don't - one can > >unambigiously define plenty of things using a procedural definition. > > In part it's probably that mathematics has a widely-used notation > for declarative definitions, but not for procedural ones. That's because mathematicians wanted to present work the declarative way, not the procedural way - but you get to the declarative outcome via a procedure. The point of the declarative approach is so you can present a stunner without letting on how to got there - it's just swank on the part of mathematicians (et al.) if you ask me to present stuff that way, pure swank. > But the boundary isn't clear: you can write declarative definitions > that reflect the procedure quite closely. We could say: > > Given a relation R (e.g. the is-a-parent-of relation), define R2 such > that C R2 A iff C R B and B R A (R2 is the is-a-grandparent-of > relation). Ah - now that's /fairly/ plain. Less obscure than the usual way of expressing things - but I can't guess where you're going from here which means there's a flaw in the approach somewhere. > In general, define Rn such that X Rn Z iff X R Y and Y R(n-1) X (Rn is > the is-an-nth-generation-back-ancestor-of relation). X is the nth gen ancestor of Z if and only if X is the parent of Y and Y Y is the (n-1)th generation ancestor of X. (But what does nth-generation-back-ancestor mean? Back ancestor? What's a a tautology like that doing in here?) > Then define R' to be the union of R and all the Rn (your ancestors are > your parents, your grandparents, your great-grandparents, your > great-great-grandparents, ...). Umm - I think you're abbreviating again here. Could you expand? How can you make a union set between two binary relations and expect it to contain the results of > >> As I've probably remarked before, "The Origin of Consciousness in > >> the Breakdown of the Bicameral Mind" is good on metaphors, even if > >> you don't accept its main thesis. > > >Since my first big problem with that book is its apparent tacit > >acceptance of real meaning belonging to the word `consciousness' > > A large portion of the book is devoted to discussing what, if > anything, consciousness is. > > >Another point is that I'm generally not keen on metaphors for anything > >much except humour or illustrating things about people to people > >directly in the real-life face-to-face happening-now conversational > >world. > > If I can say this without causing offence, I think it's quite likely > that certain kinds of mental illness might make it harder to deal with > metaphors. That's just plain ignorant - do not dismiss variations in psychology and outlook and mental development as `mental illness'. Autism and Aspergery's syndrome - in /some/ variations - can better be called mental differences than mental illnesses. > The thesis of the book is that metaphors are central to > modern consciousness, Yes, to which I say `discussing consciousness is a waste of time and a distraction from the real business of figuring out what can be figured out abotu the concept we refer to as `the human mind' '. > and draws parallels between schizophrenia and > the conjectured organisation of the mind before modern consciousness > developed. Whether any of that is true is still a matter of debate. Shouldn't be, because there's nothing real to talk about on the subject. > >3) It's called the closure because you go on until you don't get any > >new elements - the resulting set is closed. > > > >That one, I'm still mildly baffled about. Can you expand? > > A set is called "closed" under an operation if applying the operation > to an element of the set always gives you an element of the set. Heh - learnt that for O level, forget it, you just reminded me. > The set of you and your parents is not closed under the is-a-parent-of > relation, because your parents' parents are not in it. Ah - yes, yes, straightforward. Umm. Or maybe not. Go on, can you express that in a full form? I'm not quite seeing how it works, if you dig what I'm getting at man. Best I don't ask any more until you've given it a bash - I've got some horribly messy ideas I could explain, but why bother 'cos they're obviously wrong? > The set of > you and your ancestors *is* closed under that relation. Using the definitions here, yes. Using real biology, no. > (I realise I'm conflating the closure of the set under the relation, Okay, now this has lost me. I was okay up until here. > i.e. you and all your ancestors, with the closure of the relation, > i.e. the is-an-ancestor-of relation.) Lost again - sorry, I don't get that at all. Totally lost - I /was/ following you, but `with the closure of that relation'? I thought you'd explained that closure was something that applied to a set under a relation How can a relationship have closure in the sense of a set being closed? And how come transitive closure is a term that applies to ordered pairs specifically, or have I got that wrong? > >`In psychology, bicameralism is a hypothesis which argues that the human > >brain once assumed a state known as a bicameral mind in which cognitive > >functions are divided between one part of the brain which appears to be > >"speaking", and a second part which listens and obeys.' > > >- it's a psychological hypothesis from a professional psychologist. > >Which means it's almost certainly total bollocks. > > Quite possible, but it's really rather interesting bollocks. I lost interest in that kind of thing a very long time ago when I noticed that it was all just, just - filling up space for the sake of it, not actually dealing with anything but lunatic hypotheses which seem to have no points of contact with the universe I observe. I'm perfectly seriously when I say that having met quite a few psycho-professionals, most of them are dangerously out to lunch. And I do mean *most* of them. Rowland. -- Remove the animal for email address: rowland.mcdonnell(a)dog.physics.org Sorry - the spam got to me http://www.mag-uk.org http://www.bmf.co.uk UK biker? Join MAG and the BMF and stop the Eurocrats banning biking |