I've recently made a startling discovery that explains a LOT about how kmemcheck has been working (or not) on one of my machines.Yesterday I added the kmemcheck hooks into the DMA API, which means that we should now not give any false-positive errors about DMA-able memory. The patch was essentially a one-liner, since the rest of the DMA API deals...

Yesterday, I decided that it was time to try out Fedora 9; after all, it's been a few months since it was released, and having just made a backup, I found that this was a convenient time to perform the upgrade.Things did not start out so well, though. The installer seemed incredibly slow this time. There is a progress bar which shows how many...

I watched updates from the 2008 WWDC Keynote through my Nintendo Wii! And why not?

/**/ One thing I noticed ever since getting a multi-core system was that the reference FLAC encoder is not multi-threaded. This isn't a huge problem for most people as you can simply encode multiple files at the same time but I usually rip my audio CDs into a single audio file with a cue sheet instead of separate track files and so I am usually...

Okay, I lied; you can't really embed brainfuck in C++ but you can get pretty close. Here is an example: #include "bfpp.h" int main() { // Prints out factorial numbers in sequence. Adapted from // http://www.hevanet.com/cristofd/brainfuck/factorial.b . bfpp * + + + + + + + + + + * * * + * + -- * * * + -- - -- & & & & & -- + & & & &...

I’m off to Tartu in late August, for what looks like a really fun conference on logical pluralism. The list of speakers is extraordinarily high-powered. Having so many smart people talk about logical pluralism is exciting, and not a little bit scary. If you’re interested in coming along, let the organisers know by July 1. If you’re interested in...

The journal Informal Logic, on argumentation theory and related issues, is now open access and online, after a 27 year history as a print (closed access) journal. The editors have sent out a request for interested parties to subscribe. Subscription is free: just fill in this form on the site. The editors are aiming get enough subscribers to...

Alas, we are in the news for not-very-good reasons. Given the recent retirements in Philosophy at Melbourne, it would be worse than surprising if any of the new redundancies hit Philosophy. However, the atmosphere around here not good – what concerns us most is the scope for new hiring when the Faculty as a whole is in the red so much. It is very...

For some time now, many of us around MIT have noticed just how awesome sshfs is. It gives a totally lightweight way to access the remote filesystem of any machine you have ssh to, without requiring any extra setup on the host. I’ve been running for at least a year now with my /data RAID on my server sshfs-mounted on my laptop, and it works...

I’ve recently switched to Conkeror as my primary browser. It started life as a Firefox extension, but nowadays it’s a standalone app built on top of Mozilla’s xulrunner, so it uses the Gecko rendering engine. What it is, is an emacs implemented in Javascript, for the web. This means on the one hand that it acts like emacs. Most of the basic emacs...

"Well," he began, moving closer to her, "declarative programming is when you tell the computer what you want, and then the computer figures out how to get it. Pretty sweet, huh?" "What kinds of things can you tell the computer you want?" she asked excitedly, her cheeks beginning to flush. He thought for a moment, and began stroking her hair...

We diagnose the two envelope “paradox”, showing how the indifference principle plays a role in prompting the conflicting assignments of the expected outcomes for switching or keeping.

I point out that non-classical “solutions” the paradoxes of self-reference are non-particularly easy to give. Curry’s paradox is very very hard to avoid, if you wish to give a semantically cohrerent picture.

In this short paper, I compare and contrast the kind of symmetricalist treatment of negation favoured in different ways by Huw Price (in “Why ‘Not’?”) and by me (in “Multiple Conclusions”) with Robert Brandom’s analysis of scorekeeping in terms of commitment, entitlement and incompatibility. Both kinds of account provide a way to distinguish the...

We argue that the participatory language, used in the New Testament to describe the the efficacy of Jesus’ death on the cross, is essential for any understanding of the atonement. Purely personal or legal metaphors are incomplete and perhaps misleading on their own. They make much more sense when combined with and undergirded by, participatory...

broder has been hacking on some better quicksilver integration for Hiveminder using todo.pl. I don’t use a mac, but I don’t see why linux users shouldn’t get fun toys to. So I hacked up the following two-liner that uses todo.pl and ratmenu to pop up a list of tasks, and mark one as completed: #!/bin/sh todo.pl | perl -ne 'push @a,$2,"todo.pl done...

This has been a good day. (Here is the video — in three parts.) As PJK said, when you change the government, you change the country…

I’ve had a new iPhone for about a week now, so I figure it’s time to write up some thoughts about it. First, the little things. It is, in typical Apple fashion, an incredibly slick piece of work. Scrolling and zooming images or webpages is simple, easy, and, well, just fun to do and watch. Mobile Safari does a great job of making full webpages...

This solid volume with the ominous black cover and eerie glowing disc lettered with inscrutable strings of characters such as “DNdQ,” “LSDJd,” and “L2LDJQ±” is the fruit of over 30 years of Ross Brady’s logical labours. And it is worth the wait…

/**/ function trackOutboundLink(url) { ga('send', 'event', 'outbound', 'click', url, { 'hitCallback': function() { document.location = url; } }); } Another interesting problem I stumbled across on reddit is finding the longest substring of a given string that is a palindrome. I found the explanation on Johan Jeuring's blog somewhat...

Modal logic is a well-established field, and the possible worlds semantics of modal logics has proved invaluable to our understanding of the logical features of the modal concepts such as possibility and necessity. However, the significance of possible worlds models for a genuine theory of meaning–let alone for metaphysics–is less clear. In this...

Are you an undergraduate student in philosophy, or do you know any undergraduate philosophy students? If so, you might be interested in the Melbourne Philosophy Undergraduate Workshop to be held from September 21 to 23. This will be a chance for Australian and New Zealand undergraduate students who are interested in philosophy, to get together to...

I’m sitting in the airport in Las Vegas on the way back from DEF CON 15. It’s the first time I’ve been at the con, and it wasn’t really what I expected. Frankly, I walked away feeling kinda underwhelmed. Very few of the talks were as technical as I was hoping – they were almost universally broad overviews of an area, with lots of introduction,...

I gave a talk on Logic in Australia at Monash University’s Arts in Action festival in early June. (This was a part of a long-running project on a History of Australasian Philosophy. The talk is now appearing, in two parts, on the (wonderful) ABC Radio National program, The Philosopher’s Zone. The first part was broadcast this weekend, but the...

I’ve been back in Melbourne for a while. The trip was very enjoyable, but I’ve returned to Melbourne with a chest bug, which has meant that I’m not quite up to full speed yet. All non-essential activities (and alas, some essential ones, I fear) are progressing much more slowly than usual. Here are some highlights of the trip. Logica 2007 with so...

// See https://github.com/Khan/KaTeX/issues/85 . KaTeXMacros = { "\\cfrac": "\\dfrac{#1}{#2}\\kern-1.2pt", }; I encountered an interesting problem on reddit a few days ago which can be paraphrased as follows: Find a perfect square \(s\) such that \(1597s + 1\) is also perfect square. After reading the discussion about implementing a...

I’ve arrived in a sunny and summery Prague. The locals tell me they it’s cooler than the unseasonably warm that it’s been in the last few years, but it seems nicely summery for one who has come from a winter. I’m now chatting in the office with Timothy, Jarda and Vladimir, and monopolising Jarda’s computer while the others do work preparing for...

I’m waiting in Gate 9 at the international terminal Melbourne Airport, getting ready to board my first flight on my trip to Europe. It’s not a short hop – Singapore/Frankfurt/Prague, but at least I’ll be in a very nice place for what to all appearances will be a very enjoyable conference. From then, it’s Bonn, and then Denmark (København, and...

You learn something new every day. What we mistakenly called gargoyles are actually finials. (I’ve corrected the caption on the photo – in case you don’t understand what Christine meant.) Christine took that photo on a finial-photographing expedition with Zachary and a friend from his class in school, on Zachary’s birthday a few weeks ago.

As I’ve said before, logic jobs in Philosophy Departments are pretty rare. Well, as Richard mentioned earlier, there’s a logic job in Philosophy at Auckland. A little bird has told me that even though the deadline is close (May 18), they’re keen to get the word out to get as many applicants as possible. So, if you qualify (PhD or equivalent in...

You’ve probably worked it out, but I’m no longer working on SMIL at the moment. tor has very kindly helped out and has been doing some work on this but it will not make it for Firefox 3. From now on, if you want to track the progress of SMIL in Mozilla I recommend: \#216462 Implement SVG (SMIL) Animation tor’s weblog

The program for Logica 2007 has been released, and it looks great. It looks like it will be seriously good, and it will be my first ever conference held in a monestery.

This Tuesday, I’m going to a party: It’s a launch for Christine’s book Inside Lawyers’ Ethics, which she’s coauthored with Adrian Evans from Monash Law School. The book will be launched by Louise Sylvan, from the ACCC. This party will be held at the Monash University Law Chambers in the city. Congratulations, Christine and Adrian! It seems to be...

1007 words on symbolic logic – concentrating on the history of 20th Century logic, aimed at an audience of social scientists

In this paper I introduce a sequent system for the propositional modal logic S5. Derivations of valid sequents in the system are shown to correspond to proofs in a novel natural deduction system of circuit proofs (reminiscient of proofnets in linear logic, or multiple-conclusion calculi for classical logic). The sequent derivations and proofnets...

Second order quantification is puzzling. The second order quantifiers have natural and compelling inference rules, and they also have natural models. These do not match: the inference rules are sound for the models, but not complete, so either the proof rules are too weak or the models are too strong. Some, such as Quine, take this to be no real...

Liveblogging talks was a bit beyond me, but I’ve been keeping up with a few notes on the talks here in Banff. They’re not as extensive as my notes on Branden and Delia’s talks, but they’ll give you an idea of the fun we’ve been having here. (After lunch today, there’s a batch of five talks, including mine. I’m not sure when I’ll be able to write...

I’ve finished up the slides for my talk in Banff. If you’re interested, the slides are available here Modal Models for Bradwardine’s Truth [1.3MB pdf] It’s a talk giving a modal logic interpretation for a medieval theory of truth due to Thomas Bradwardine, as it’s reconstructed by Stephen Read. This will hopefully help out Steve’s project, by...

The next Banff talk is Delia Graff Fara, on “Relative identity and de re modality.” She’s defending the thesis that material objects are identical to the matter of which they’re constituted. For example, the statue Goliath (G) is identical to the lump of clay Lumpel (L). She wants to allow that L = G, while having L and G differing in their...

The first talk in Banff is by Branden Fitelson, who is giving a ‘“Survey” of Formal Epistemology: some propaganda, and an example’. It’s a part of the general movement towards carving out the discipline of ‘formal epistemology’. It’s a partly political talk, recounting the motivation for Formal Epistemology. He recounted Bob Meyer’s manifesto of...

I’m in sunny and wintry Banff at the Mathematical Methods in Philosophy workshop. The program is very full, and I won’t be able to report on everything going on here. (Heck, I haven’t even reported back from our time in India, despite popular demand.) So, please let me give my apologies in advance if youre talk doesn’t get reported here. It’s...

I’m taking 6.170 Lab in Software Engineering this semester. The course sucks in various ways, but one of the most egregious, in my opinion, is that they force you to use CVS for your version control. Problem sets are distributed by the TAs importing them into your repository, and are then checked out later to be graded. Well, CVS sucks, and...

I’ve been having too much fun and doing too much work lately to post anything here. On the work side, our proposal to teach first-year logic in an interdisciplinary way as a “breadth” subject to all students in the “new generation” degrees from 2008, has passed the first hurdle. We have a bucket of money to develop the course over the next year....

My son, Z, asks me Dad, what is Kantian freedom? some time later Dad, what is a conceptual repertoire? No, he’s not a philosophical prodigy. He was curious about what I was reading, and I explained that I had an essay written by a student, and I had to figure out how good it was. It happened to be an essay about John McDowell’s Mind and World,...

Two bits of horn tooting for today: First, from the famous and notorious Philosophical Gourmet Report. Brian Leiter pointed out that the report hit the newspaper here in Australia. The point of the little note in the Higher Education section of The Australian was that the ANU topped the rankings of Australian philosophy departments (as it has in...

I’d like to guage some philosophical opinions. (I don’t have many of my own. Most of them have been worn down by years of logical abuse.) First, some pre-requisites: Let’s understand ‘possibly’ as a metaphysical sort of possibility. If it helps, think of it as truth in some possible world, no matter how outlandish. Let’s understand a priori...

You’re all invited to a party on Tuesday, October 17 (5:30pm for 6pm) at the Melbourne University Bookshop to celebrate the publication of five books in Logic and Philosophy here in the Philosophy Department at Melbourne. Here are the books: Models, Truth and Realism, Barry Taylor. Doubt Truth to be a Liar, Graham Priest. In Contradiction, Graham...

Here’s my (much delayed) answer to the second of Vincent Hendricks and John Symons’ five questions about Formal Philosophy. What example from your work illustrates the role formal methods can play in philosophy? I’ll focus on one example from some of my recent work. In the last few years I have been working on topics in proof theory and...

I just had an Idea today. From here, it seems like a Really Neat Idea. (Having the idea made me remember what it feels like to prove something you’ve been struggling with for a long time: a mix of excitement, wonder, awe, relief, and much else besides. It’s welcome to be reminded of why I like working in logic.) This idea isn’t a new theorem, but...

In the Philosophy Department we’re pleased to be hosting some short visits from Gillian Russell, and Jon Cohen. It’s neat to be in a place where smart people come to visit, think and talk to you. Last week we had a couple of logic seminars from neat west-coast of the USA types: Mike Titelbaum from Berkeley and Stanley Peters from Stanford. At...

Since Jo asked so nicely, I’ll add my answers to the one book meme that’s going around the place. One book that changed your life Robert C. Roberts, Spirituality and Human Emotion. It’s because of this book that I’m a philosopher, believe it or not. Reading it, I saw that the philosophy needn’t be self-contained, but could be used to say...

Wow, what a heading! Some would call it lack of imagination, I like to think of it as artistic restraint — it’s just too easy to make puns with “SMILe”! Progress on SMIL continues, albeit in slow motion. Just a really quick note for those one or two people who want to know what’s going on:

I’ve listened to the interview, and I’m pretty happy with how it went. The ABC team did a good job with the editing (I think the interview I recorded was a bit over 30 minutes). I never thought that I’d live to hear the day that someone explained the semantics of first degree entailment on national radio, and I was especially grateful that my...

In the car this evening, Z (our five-and-a-bit year-old son) says, unprompted, Dad, I’ve been thinking … I reply “yes …” … why does Kim Beazely want to be Prime Minister? It’s nice to know that he’s keeping up with his world. It’s telling that we found it difficult to answer the question.

This morning I trooped down to the ABC Melbourne studios in Southbank, to sit in a ‘Tardis’ booth to talk to Alan Saunders of The Philosopher’s Zone on logic, the liar paradox and other stuff I think about. Alan was feeling unwell and suffering from a croaky voice, so the interview that goes to air might be more of a monologue than what took...

It’s been difficult to get back into the swing of work, but I’m slowly clawing my way through. Jetlag has been much worse on my return than on the European end of the trip. I’ve also been concentrating on my parental duties, as my Significant Other is taking her conference trip. Playing with your son is much more fun than doing niggly...

I’m back in Melbourne, after my whirlwind jaunt in Nancy. I was in too much of a rush on Day 4 of the conference to post thoughts on Day 3 or Day 4. I promise I’ll do that once I recover from my jetlag and deal with my growing pile of mail, both snail and electronic. In other news, the nicest thing about reading this article on blogging in this...

Nancy Day 2 was a quiet as far as the official program went. Talks were scheduled in the morning leaving the afternoon free. Michael Lynch and I took in the Musée des Beaux-Arts and talked philosophy and much else with Peter van Inwagen, Scott Shalkowski and others into the evening and late in the night. The morning featured a well-put-together...

I’m conference blogging here in Nancy at the Realism/Anti-Realism conference. It’s been neet, chatching up with people I’ve not seen for a while. Today, after a not-completely-rested-night as I tried to sleep through a rather rowdy French community beeping car horns after their 3-1 victory in the round of 16, I went to five talks. Here’s the...

Today I’m flying off to Nancy for (Anti)Réalismes Logique & Métaphysique. It should be an interesting meeting: the program is here. If I get time to edit my paper on the plane, I’ll try posting the text of the paper before I give it, internet access permitting.