The Definition of Points
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From: Brian Chandler on 31 Mar 2007 10:07 Tony Orlow wrote: > stephen(a)nomail.com wrote: > > In sci.math Virgil <virgil(a)comcast.net> wrote: > >> In article <460d4813(a)news2.lightlink.com>, > >> Tony Orlow <tony(a)lightlink.com> wrote: > > > > > >>> An actually infinite sequence is one where there exist two elements, one > >>> of which is an infinite number of elements beyond the other. > >> > >> Not in any standard mathematics. > > > > It is not even true in Tony's mathematics, at least it was not true > > the last time he brought it up. According to this > > definition {1, 2, 3, ... } is not actually infinite, but > > {1, 2, 3, ..., w} is actually infinite. However, the last time this > > was pointed out, Tony claimed that {1, 2, 3, ..., w} was not > > actually infinite. > > > > Stephen > > No, adding one extra element to a countable set doesn't make it > uncountable. If all other elements in the sequence are a finite number > of steps from the start, and w occurs directly after those, then it is > one step beyond *some step* which is finite, and so is at a finite step. Perhaps you might care, Tony, to list some properties of this "some step" you have referred to above? I tell you what, I'll give you a start - let's call this 'step' (actually this is the wrong word, since step is normally the gap between two adjacent elements**, so let's call this element) Q. ** I'm sure you understand that being described as more logically coherent (orwhateveritwas) than Lester Zick is rather like being called more caring than Jack the Ripper, but I take the sentiment to mean that you will probably agree with this nitpick about 'step' terminology. So: Q has the property of being the last element in an endless sequence Q has the property of nonexistence, actually Now it's your turn. > Try (...000, ..001, ...010, ......, ...101, ...110, ...111) Why? What is it, anyway? Brian Chandler http://imaginatorium.org
From: Mike Kelly on 31 Mar 2007 10:27 On 31 Mar, 13:41, Tony Orlow <t...(a)lightlink.com> wrote: > Mike Kelly wrote: > > On 30 Mar, 18:25, Tony Orlow <t...(a)lightlink.com> wrote: > >> Lester Zick wrote: > >>> On Thu, 29 Mar 2007 09:37:21 -0500, Tony Orlow <t...(a)lightlink.com> > >>> wrote: > >>>>>> If n is > >>>>>> infinite, so is 2^n. If you actually perform an infinite number of > >>>>>> subdivisions, then you get actually infinitesimal subintervals. > >>>>> And if the process is infinitesimal subdivision every interval you get > >>>>> is infinitesimal per se because it's the result of a process of > >>>>> infinitesimal subdivision and not because its magnitude is > >>>>> infinitesimal as distinct from the process itself. > >>>> It's because it's the result of an actually infinite sequence of finite > >>>> subdivisions. > >>> And what pray tell is an "actually infinite sequence"? > >>>> One can also perform some infinite subdivision in some > >>>> finite step or so, but that's a little too hocus-pocus to prove. In the > >>>> meantime, we have at least potentially infinite sequences of > >>>> subdivisions, increments, hyperdimensionalities, or whatever... > >>> Sounds like you're guessing again, Tony. > >>> ~v~~ > >> An actually infinite sequence is one where there exist two elements, one > >> of which is an infinite number of elements beyond the other. > > >> 01oo > > > Under what definition of sequence? > > > -- > > mike. > > A set where each element has a well defined unique successor within the > set. So any set is a sequence? For any set, take the successor of each element as itself. > Good enough? You tell me. Did you mean to say "a sequence is a set"? If so, good enough. -- mike.
From: Mike Kelly on 31 Mar 2007 10:29 On 31 Mar, 13:48, Tony Orlow <t...(a)lightlink.com> wrote: > step...(a)nomail.com wrote: > > In sci.math Virgil <vir...(a)comcast.net> wrote: > >> In article <460d4...(a)news2.lightlink.com>, > >> Tony Orlow <t...(a)lightlink.com> wrote: > > >>> An actually infinite sequence is one where there exist two elements, one > >>> of which is an infinite number of elements beyond the other. > > >> Not in any standard mathematics. > > > It is not even true in Tony's mathematics, at least it was not true > > the last time he brought it up. According to this > > definition {1, 2, 3, ... } is not actually infinite, but > > {1, 2, 3, ..., w} is actually infinite. However, the last time this > > was pointed out, Tony claimed that {1, 2, 3, ..., w} was not > > actually infinite. > > > Stephen > > No, adding one extra element to a countable set doesn't make it > uncountable. If all other elements in the sequence are a finite number > of steps from the start, and w occurs directly after those, then it is > one step beyond some step which is finite, and so is at a finite step. So (countable) sequences have a last element? What's the last finite natural number? -- mike.
From: stephen on 31 Mar 2007 11:04 In sci.math Tony Orlow <tony(a)lightlink.com> wrote: > stephen(a)nomail.com wrote: >> In sci.math Virgil <virgil(a)comcast.net> wrote: >>> In article <460d4813(a)news2.lightlink.com>, >>> Tony Orlow <tony(a)lightlink.com> wrote: >> >> >>>> An actually infinite sequence is one where there exist two elements, one >>>> of which is an infinite number of elements beyond the other. >>> >>> Not in any standard mathematics. >> >> It is not even true in Tony's mathematics, at least it was not true >> the last time he brought it up. According to this >> definition {1, 2, 3, ... } is not actually infinite, but >> {1, 2, 3, ..., w} is actually infinite. However, the last time this >> was pointed out, Tony claimed that {1, 2, 3, ..., w} was not >> actually infinite. >> >> Stephen > No, adding one extra element to a countable set doesn't make it > uncountable. Who said anything about uncountable? You said: >>>> An actually infinite sequence is one where there exist two elements, one >>>> of which is an infinite number of elements beyond the other. No mention of uncountable. > If all other elements in the sequence are a finite number > of steps from the start, and w occurs directly after those, then it is > one step beyond some step which is finite, and so is at a finite step. So you think there are only a finite number of elements between 1 and w? What is that finite number? 100? 100000? 100000000000000000? 98042934810235712394872394712349123749123471923479? Which one? It should be obvious that the number of elements between 1 and w is larger than any finite natural number. Let X be a finite natural number > 1. Then {2, 3, .. X, X+1, .. 2X } is a subset of the elements between 1 and w that has more more than X elements. As I said, even you do not accept your own definition of "actually infinite". Stephen
From: Tony Orlow on 31 Mar 2007 11:41
Brian Chandler wrote: > Tony Orlow wrote: Hi Imaginatorium - >> stephen(a)nomail.com wrote: >>> In sci.math Virgil <virgil(a)comcast.net> wrote: >>>> In article <460d4813(a)news2.lightlink.com>, >>>> Tony Orlow <tony(a)lightlink.com> wrote: >>> >>>>> An actually infinite sequence is one where there exist two elements, one >>>>> of which is an infinite number of elements beyond the other. >>>> Not in any standard mathematics. >>> It is not even true in Tony's mathematics, at least it was not true >>> the last time he brought it up. According to this >>> definition {1, 2, 3, ... } is not actually infinite, but >>> {1, 2, 3, ..., w} is actually infinite. However, the last time this >>> was pointed out, Tony claimed that {1, 2, 3, ..., w} was not >>> actually infinite. >>> >>> Stephen >> No, adding one extra element to a countable set doesn't make it >> uncountable. If all other elements in the sequence are a finite number >> of steps from the start, and w occurs directly after those, then it is >> one step beyond *some step* which is finite, and so is at a finite step. > > Perhaps you might care, Tony, to list some properties of this "some > step" you have referred to above? I tell you what, I'll give you a > start - let's call this 'step' (actually this is the wrong word, since > step is normally the gap between two adjacent elements**, so let's > call this element) Q. I'll give *you* a start, Brian, and I hope you don't have a heart attack over it. It's called 1, and it's the 1st element in your N. The 2nd is 2, and the 3rd is 3. Do you see a pattern? The nth is n. The nth marks the end of the first n elements. Huh! So, the property I would most readily attribute to this element Q is that it is the size of the set, up to and including element Q. That is, it's what you would call aleph_0, except that would funk up your whole works, because aleph_0 isn't supposed to be an element of N. Take two aspirin and call me in the morning. > > ** I'm sure you understand that being described as more logically > coherent (orwhateveritwas) than Lester Zick is rather like being > called more caring than Jack the Ripper, but I take the sentiment to > mean that you will probably agree with this nitpick about 'step' > terminology. Surely, you don't think me fool enough to think that Virgil would actually give me a sincere compliment, or acknowledge that any of my nonstandard points actually has any merit, do you? Still, it was nice of Virgil to say I'm not worst ignoramus he knows. That warmed my heart. Still, I don't know what Virgil's comment about me says about my future responses to you. See above for a characterization of Q. > > So: > > Q has the property of being the last element in an endless sequence > Q has the property of nonexistence, actually > > Now it's your turn. > > > n has the property of being the size of the sequence up to and including n. >> Try (...000, ..001, ...010, ......, ...101, ...110, ...111) > > Why? What is it, anyway? Google 2-adics. > > Brian Chandler > http://imaginatorium.org > Tony Orlow http://realitorium.net |