Typing passwords is bad. Typing passwords on anything other than your local machine is really bad. Here’s how to use a nice little library to authorise your use of sudo via your already-running SSH agent.

Quick overview: If you are using SSH properly you are using ssh-agent (or gpg-agent) to login to remote servers. Presumably you trust machines you have sudo access on enough to use SSH agent forwarding, so, when SSHing, the remote machine can pull authentication info from your local agent (perhaps popping up a password dialog locally if needed) to use elsewhere. Well, why not require that same information to sudo? If it can pull the authentication, it’s definitely you on your local machine who’s typing the sudo command.

,# apt-get install libpam0g-dev libssl-dev

Download pamsshagentauth. Extract to wherever you put things you are make && make install’ing on your server, then

$ ./configure
$ make
,# make libexecdir=/lib/security install

Now edit the file /etc/pam.d/sudo to replace the line @include common-auth with

auth sufficient pam_ssh_agent_auth.so \
file=%h/.ssh/authorized_keys
auto required pam_deny.so

Finally visudo and add before the Defaults env_reset line

Defaults env_keep += SSH_AUTH_SOCK,timestamp_timeout=0

This makes things work and also removes sudo remembering your authentication—it’s your SSH agent’s job to do that.

sources: 1, 2

Posted Wed 01 Feb 2012 00:22:00 UTC Tags:

From an all-students e-mail:

Non-Emergency Police Number 101

The number for the Non-Emergency Police (Thames Valley) has changed to a new National Number which is 101. The old number 08458 505505 will be discontinued after 31 March 2012. University of Oxford student cards that were issued prior to this notified change in number will display the old number until those cards expire.

Good to see the university letting us know that they can’t remotely edit our plastic cards.

Posted Wed 01 Feb 2012 10:52:00 UTC Tags:

Just came back from a talk by Hin-Tai Ting from one of the brave few philosophy students who chose to write a thesis in place of a finals paper, 15 000 words on the problem of evil. Firstly the problem is analysed down to whether or not there exists a moral evil which god has no morally sufficient reason to allow; if there is no such evil, then the famous impossible triangle of infinite love, infinite power and infinite knowledge dissipates. To do this Ting draws upon Christian doctrine, looking at Jesus’ death at the hands of the Romans; he explained that this isn’t something that’s been done before (I presume the analysis above is standard in philosophy of religion?). The impossible triangle is all about an inconsistency. If this inconsistency is not real then the problem of evil is no longer an argument against (Christian) theism, when the argument is taken to be saying that said theism is inconsistent in some way and we should never accept an inconsistent theory.

The philosophical interest for me is in this overall process. Using a thought experiment about an explorer and a series of notebooks, and a second version of this modified to help the argument along, imaginative fantasies very much in keeping contemporary philosophical style, we discussed whether this methodology was legitimate. The worry is that in invoking Christian doctrine to respond to the problem of evil, we are assuming just what we are trying to prove since the problem of evil says that all this doctrine is false. On the face of it it doesn’t seem to actually be a problem. By looking at things in terms of consistency as I described above, everyone in the room was of the opinion that the methodology was sound, including myself, but I wanted to investigate further because the second thought experiment had me worried.

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Posted Wed 01 Feb 2012 22:35:00 UTC Tags:

I frequently post on this blog about things I want to achieve, more specifically, good habits of life I want to acquire. Many of these I fail at, I drift off target, I don’t get sorted. However even if I get a sense of failure at the time I’ve realised that a lot of them sink in anyway, simply by telling myself that it’s good enough times, it becomes good. And then randomly at some future date, I’ll suddenly start acting perfectly in line with the habit, and then a few days into this I’ll realise, and realise how effortless it is, and feel wonderful about this fact.

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Posted Thu 02 Feb 2012 15:11:00 UTC Tags:

You might say I am ‘engaged’ with my philosophy today. I just went to have lunch in Hall and my fellow mathematicians found that I’d lost the ability to eat: I spilled water down myself, dropped my dessert into my lap, sent my tray careering precariously about. Then on our way out I slammed open the door very hard, and had to use the rail to get down the stairs safely. My friends were worried about me making it to the Philosophy Faculty safely.

Let me stress that this is in no way put on. These were not me consciously expressing my agitation: I just found myself making these simple practical mistakes. The only conscious part is choosing to take the staircase very carefully, when I usually sprint up and down it.

My essay topic is innocuously titled, are moral judgements subjective or objective, but I’m being convinced that there are massive issues across philosophy going on here. This has been brought about by reading a textbook-like book by David McNaughton. Every paragraph is trite and obvious, but what it does is put the different authors in the debate in a framework, which allows you to engage with it—when these authors are hard to read, your mind doesn’t have time to work on relating them to each other sometimes.

So my current overwhelming thought is that Plato was so very, very wrong with his dictum that what philosophy is doing was separating appearance from reality, and the claim that this is the most important thing. Perhaps his metaphysics still works for maths but not much else. It’s Nagel vs. the prevailing naturalism of our time, no, more than that, it’s Hume vs. Kant, it’s the question of whether or not the realisation of just how much we put into experience to make it possible makes the Humean position implausible.

My fellow students are laughing at me which I think is the only appropriate reaction. Good philosophy does not get done in this state. But it remains an expression of its importance.

Posted Fri 03 Feb 2012 13:59:00 UTC Tags:

… is really good, go and see it. Main character brilliantly played.

Posted Sat 04 Feb 2012 23:42:00 UTC Tags:

I am very disappointed in myself this evening. I went along to a talk from a series about meeting Jesus run by the university Christian Union, and my reaction upsets me. For the past three or four years I have managed to actually be an agnostic, the appropriate extension of my scepticism into the arena of religion. When talking with religious people I have experienced a clash of upbringing more than anything else. That seemed to be the drive behind religious belief. So it was an interesting thing to discuss, and I managed to remain fairly sceptical. But recently this is collapsing and esp. tonight. I’m getting angry with people for their theism. That’s the issue. The belief in a god. But this doesn’t fit because I try to keep my epistemological commitments minimal: it’s no different to realism vs. idealism w.r.t. the external world. So if I’m not going to get angry with people committed to that world (which probably includes myself), I shouldn’t get angry with theists either.

Yet I am doing and in the worst way possible. This speaker tonight was attempting to engage with Oxford students by saying that people aren’t open-minded enough about Christianity; appealing to the intellectual virtue of open-mindedness. Good. An open mind is appropriate for the sceptic, even on the issue of his scepticism. My reaction? A retreat to a pathetic construction of rationality invoking words like “Socrates”, “the Academy”, “analytic philosophy”. What do I know about any of these things? Very little, and in any case, invoking them like this is attaching oneself to things in a dogmatic and uninteresting way.

The correct response? Try to charitably construct a consistent story from the opposition. Help them to do this. Use one’s philosophical training. Then place it alongside all the other worldviews available, compare and contrast, come to understand the things we know and don’t know about the area better. Very far removed from tonight’s arrogance from me.

Posted Tue 07 Feb 2012 22:48:00 UTC Tags:

Here’s the piece on Trefethen’s Index Cards I talked about recently.

The idea of an intellectual carrying around a notebook, filling it with the thoughts that arise in his mind from day-to-day, has been capitalised on in recent years by various companies. The market for serious-looking notebooks confronts us in every bookshop. Many people buy notebooks with this purpose in mind but not many have them published. And historically, famous thinkers whose notebooks have ended up being published, such as Quine, Samuel Butler and Georg Lichtenberg, have only managed twenty or thirty years worth of notes at best.

These facts make Balliol’s Nick Trefethen, University Professor of Numerical Analysis, quite unique. Since 1970 when he was 14, Trefethen has been typing down his thoughts onto index cards, initially at 3”x5”, at some point switching to 4”x6” which he has used ever since, now writing roughly two or three per month. After fourty years of writing cards, Trefethen has made a selection of them public as Trefethen’s Index Cards, published by World Scientific this year.

There is a striking consistency of quality throughout the cards: they all show that Trefethen is a master of concise expression. While the index card format was initially just a convenient way to store the cards, it became a constraint, forcing a training in conciseness. Trefethen writes, ‘Once I’ve put an idea on a card, it becomes a piece of my mental framework, a principle I will refer to for the rest of my life.’ This consistency is also striking. Trefethen characterises the development of his thought as additive: there are very few cards containing opinions he has now turned his back on. It is thus that Trefethen’s Index Cards gives us a unique opportunity to see the complete, systematic structure of a modern scientific mind, that we can all learn something from, and will probably all find places to disagree with.

The book is organised into chapters titled by card topic, beginning with Ego, and moving through Kids, Living with Others, the Meaning of Life and then onto Politics and Society, Education, The Life of the Professor, Writing and Literature, Memory, Science, Mathematics and Computers, and more besides. Within each chapter the cards are arranged in chronological order, so when reading it’s interesting to compare the development of thought across chapters.

Trefethen’s initial motivation for the cards came from The Glass Bead Game by Hermann Hesse. This work of science fiction is set in a fictional European province dedicated to intellectual pursuits, in which economic and other material pursuits are kept to the minimum necessary. The pinnacle of scholarly pursuit within this country is playing a game with glass beads, through which all the knowledge and belief mankind has gathered through the arts, humanities and sciences is brought together. Deep connections hitherto unknown are uncovered through the process of playing.

Trefethen hoped that he might make a start on collating all knowledge in this way with his cards. He explains that as he grew older he realised that not only is it unfeasible for one man ever to collect all knowledge like this, but also that various philosophical results suggest that the task is impossible even for all humanity banded together to create a glass bead game. But the inspiration remained.

This awareness of the intellectual nature of his project is visible in other places. And the best example of this draws upon Trefethen’s profession, mathematics. On page twenty-four Trefethen says, ‘As the years go by and memory becomes less reliable, I think the habit of writing takes on a special significance. In interacting with the written page, we can edit and adjust and keep on track even at an age when on the hoof, our thoughts would ramble and we’d be at a loss to recall every third name.’

Anyone who does any kind of advanced maths recognises that a lot of work is done by the notation that has taken centuries to develop; without the ease of doing simple, routine moves purely symbolically, our minds would be too cluttered to work on the more interesting things. The thought from this index card is that this seems to apply to all other kinds of thought too, and more as one gets older. Through his cards Trefethen aims to both construct his world, and keep it safe from the ravages of time. And by publishing some of these cards he has enabled us to engage with that carefully constructed world too.

Posted Wed 08 Feb 2012 13:26:00 UTC Tags:

I want to go into academic philosophy as do several friends. This world is very mysterious to us. When you look at people publishing in journals, and you scan over journal articles treating of obscure topics, you wonder how this could possibly relate to one’s tutors here in Oxford, which always seem to be far more grounded and ethical, unconcerned with the ultra-competitiveness that pervades all modern academic life.

I think that the thing to do is to keep focussed on the three real goals of this process that are beyond desires for job security and personal recognition—the reasons one has for studying the subject. Firstly to develop one’s understanding. I imagine there are bright sparks working in philosophy because they find it fun to get published about the problems they think they’ve solved, but I’m not sure that is something that can really last. Secondly to write great essays. If one writes something fantastic, that gets undergrads and grads and faculty all excited, the name behind it is irrelevant and the journal it is published in it irrelevant—all that matters is the piece. Thirdly the importance of trying hard to teach those lower down on the path but I don’t know anything about that, being on the lowest rung…

Another mysterious fact is the relation of Oxford philosophers to the rest of the world. Philosophers seem to fall into groups, partly based on age perhaps, of people who are in touch more frequently, working on the same things. And of course everyone thinks their group is the most important. For example of the two tutors at Balliol who I know best I can give you a list of names of “their gang” of the great names of the past fifty years. I think that perhaps to a certain extent Oxford separates itself in style from, say, American universities? I really don’t know.

As students here we certainly find ourselves associating ourselves with the style of philosophy our tutors espouse. Oxford philosophy[1] is the ‘right’ kind of analytic philosophy, we think. Of course this represents a massive loss of perspective. But it’s easy to do.

Here’s another thing. Hundreds of papers get published. But as an undergrad most seem impossibly unexciting: inaccessible but also not following the big problems that to me dominate, based on my studies so far. I suppose this reflects the general inaccessibility of academic philosophy: the stuff I do is presumably equally inaccessible to the average person. It is important not to lose perspective on this too—I am very guilty of this.

[1] Not to be confused with Oxford Philosophy, a school of thought from the twentieth century.

Posted Fri 10 Feb 2012 00:51:00 UTC Tags:

A while back I got into the best productivity habit ever: don’t check e-mail before midday, and only check it twice, at around lunchtime and around teatime. And when checking it, try to be as fast as possible: make decisions, or put things on my todo list, rather than letting e-mail sit there. Exceptions on days when waiting for an important e-mail. This is a habit I have lost—time to regain it! Sticking notes on computer to remind me of this.

Posted Fri 10 Feb 2012 13:08:00 UTC Tags:

People keep saying, how is your nth week going, and I keep saying week after week “actually it’s going really really well”. I am pretty well absorbed into my work. Bad habits of procrastination still stop me from achieving quite as much as I think I’m capable of, though, but the effect is far more minor than it has been. The Pomodoro Technique is I think the main factor in this.[1] But also it’s the fact that I’m not really doing maths. There aren’t any useful lectures to go to, and the maths I am doing is easy and so it’s gratifying, and so my life each day is attending a small number of classes and just heading to the library and reading and writing philosophy, which is really great. My workload is a little less than last term too, just enough that things are more comfortable. I didn’t really realise just how much maths was making me unhappy.

continue reading this entry

Posted Sat 11 Feb 2012 21:07:00 UTC Tags:

HT12wk4 by spwhitton on SoundCloud

Here’s my set from last night; was put together pretty quickly so nothing special.

Posted Sun 12 Feb 2012 11:02:00 UTC Tags:

Coming under heavy fire from tutor at the moment for lack of conciseness. I thought I’d been getting much better at this. However I realised today that I’m missing something key. What I’m already pretty decent at is being concise in expressing particular points; writing short sentences and avoiding long words—I probably use more unnecessary long words in speech than in writing. The thing I’m missing, I think, is being concise about choosing what points to try to make at all. I tend to go the Bernard Williams write-everything-you-know-about-this approach which isn’t really very interesting.

Posted Wed 15 Feb 2012 22:52:00 UTC Tags:

Going dancing is something that I have come to enjoy enormously. There are two reasons why this is perhaps unusual. Firstly I don’t drink, and for a lot of people this seems to be a prerequisite to having fun in this way. And secondly both kinds of nerds I associate with a lot, the philosophy nerds in Balliol that don’t seem to be in many other places, and the more standard kind of nerds who like things like maths and StarCraft, tend to really dislike these sorts of environments.

continue reading this entry

Posted Thu 16 Feb 2012 00:27:00 UTC Tags:

To me this point is patently obvious but lots of people I know disagree. Also this means the primary/secondary quality distinction is legitimate.

Consider yellow, for example. We may try to define it, by describing its physical equivalent; we may state what kind of light-vibrations must stimulate the normal eye, in order that we may perceive it. But a moment’s reflection is sufficient to shew that those light-vibrations are not themselves what we mean by yellow. They are not what we perceive. Indeed we should never have been able to discover their existence, unless we had first been struck by the patent difference of quality between the different colours. THe most we can be entitled to say of those vibrations is that they are what corresponds in space to the yellow which we actually perceive. —Moore, P.E., p. 10

Posted Fri 17 Feb 2012 11:50:00 UTC Tags:

Just got back from a Physics lecture theatre to watch the live stream of a debate between Richard Dawkins[1] and Rowan Williams, chaired by Anthony Kenny,[2] and introduced by the Chancellor.[3] The topic of the debate was the ultimate origins of mankind and, eventually, the universe.

continue reading this entry

Posted Thu 23 Feb 2012 18:10:00 UTC Tags:

Just got back from watching MLG Winter Arena tonight with the Oxford StarCraft society, this is just the best thing:

evilnaniwa.png

NaNiWa is my favourite player; I like his play but also his ‘win at all costs, sanity not excluded’ attitude.

Posted Sun 26 Feb 2012 00:46:00 UTC Tags:

Radio Rivendell - The Fantasy Radio Station

This is pretty sweet, just pure fantasy music all the time, lots of fun as background. They keep playing stuff from SpellForce too :D

Posted Sun 26 Feb 2012 11:16:00 UTC Tags:

Reading about Plato’s theory of the Forms tonight. The central books of the Republic are such an enigma; it is very hard to know how to evaluate them, and all the time you’re trying to figure out just what the Cave is all about, because you realise how powerful it is, but aren’t quite sure why.

One strange thing is that in no dialogue does Plato actually argue for the existence of the Forms as, say, an explanatory device. So to say that they are an attempted solution to the problem of universals that fails isn’t fair; only a weird part of book 10 of Republic suggests that, but this doesn’t fit with the central books of Republic where we get the famous images etc. This is something I had never thought of before.

Annas suggests that reason for this is that Plato doesn’t think the Forms are something you get at purely through argument; to some extent you just have to accept it, a bit like any kind of realism: there is no argument for the external world or for the objectivity of ethical values, really, we just come to agree with these through a discussion of the concepts involved on both sides:

Hence Plato does not make it appear that our acceptance of Forms hangs entirely on our accepting certain arguments. For we might go through the proof perfectly and still fail to grasp the point of it. This is a very important point for Plato, and one to bear in mind, because here he differs considerably from modern philosophers. We should be careful not to rush to the other extreme and confuse Plato’s procedure with an easy anti-intellectualism which claims that profound truths are grasped only by direction vision or intuition, and that mere reasoning is impotent. No-one has more respect for reasoning and argument than Plato. But he is still convinced that on its own it will not produce a philosopher. —J. Annas, An Introduction to Plato’s Republic, p. 237

and

It does not matter what metaphor we use, as long as we realise that Forms are not the end of a journey of faith, beaming out certainty and security to a passive audience. They are the beginning of an intellectual quest, calling on all one’s resources to search for the truth, a journey that Plato will describe in the Cave figure as a breaking out of passive conformity to intellectual liberation. —ibid., p. 240

This is pretty cool. A philosopher is required to have a certain faith in the power of dialectic to do what he does—not in the arguments themselves, but in the approach to life that involves constantly trying to figure these things out. I am currently thinking a lot about the place of faith and reason; how much must we end up using the first—is it the case that the proper thinker (a) accepts that faith must always be playing a role (hence things like abrahamic religion end up on a similar tier to philosophy), or (b) we should always be working to eliminate any reliance on faith—though the point is that this is very hard to maintain as e.g. things like realism.

I am also reminded of J.D. Kenyon’s article Doubts about the Concept of Reason (in PAS I think) in this connection which I should probably go and read again.

Posted Mon 27 Feb 2012 21:58:00 UTC Tags: