Time and Magic

In another thread there was discussion about how well one can know 15 paces, 50 paces, diameter, etc.

I thought working out diameter duration shouldn't be too hard. Cast a follow up intelligo vim spell with a diameter duration which tells you when the target spell is half way through, and gives you a 10 second countdown before the target spell ends. I thought a magi could do the same with sun, and say have 1 hour reminders.

I then thought this would give a magi a weasely way to have a perfect clock. Each morning cast a touch sun spell, then the intelligo vim. In Mythic Europe time was hard to accurately record and measure, and this seems too easy. Also should time be encompassed by Vim? I can't think of a logical other location for Time, and Vim may be the best approximation.

Would having a perfect clock be this complicated?

E.g., if a mage casts a Creo Imagonem spell which cause a stone to light up, and which dims through the duration (e.g. cast at dusk or dawn and it is bright, fading to nothing by dusk), then that is a bit better than a pocket sundial - e.g. C J's Metal Detecting Pages - but it happens to work at night.

E.g., mage enchants a slab of stone as a magical object (Creo Imagonem) so that there is now an illusion of a tree growing from it which, as the spell progresses, sheds its leaves. This might look neat in the centre of the covenant, but really is much like a water-clock (though much cooler, but requiring vis).

If those work, then you could, if you wanted, create a variant which gave numerical representations. So, sure you could create a 2-minute magical-stopwatch if you wanted - just with CrIm or MuIm, with no need for InVi.

But in general, why would a mage want to? Knowing when a spell is about to run out would be useful, certainly. But a perfect clock? We assume that that is useful because we have constructed so much of our lives around the assumption that time should be and is minutely measured, but medieval society doesn't work that way. And the social effects of the introduction of ubiquitous and standardised mechanical time measurements were huge. So I guess I'm not sure that our characters would care, and I'm not sure it adds much to a saga.

Just FYI, in TM:RE there are spells and guidelines, and devices, to measure astrological time with high precision - which is useful if you are into astrology.
So such things exist, but for most people (including magi) they aren't important.


I have to disagree on that part. The setting of Ars Magica is right before the invention of escapements that allowed for mechanical clocks in real life (C. late 13th century) and historically it took very little time for these to lead to mechanical clocks and for that technology to see widespread adoption. It took ~30-40 years from the invention of the enabling technologies before mechanical clocks appear, and less than a decade after that before large public clock towers appear in the historical record. The people of the time really liked the idea of (relatively) accurate clocks and immediately grasped the usefulness of such.

And there are lots of reasons for this, applications of more accurate timekeeping that were immediately useful and intuitive to educated people in the 13th century. Determining the hours of prayer (a big driver behind the development of water clocks in the Islamic world in this period), various applications in astronomy, astrology, the calculation of calendars (an enduring concern of the church, who went to great lengths to calculate the occurrence of Easter), and simple day-to-day utility among others.

Would all magi realise this? No, for the reasons mentioned. Is it plausible that some magi with certain interests could realise it? Very, imo.

There are three avenues for a magus to have this realisation within the setting that I can think of off the top of my head (there might be others I'm missing):

  1. Magus has an interest in mechanical devices and has been exposed to existing mechanical clocks, which are still being actively developed at the time (water clocks in particular). These have profound limitations, so it's not a huge leap for this magus to go "I wonder could magic do better?". Particularly suited to a Verditius character, or one who has been exposed to Islamic scholarship.

  2. Magus has an interest in astrology and horoscopes, and already does a lot of calculations that are impeded by not being able to time things precisely. In this case they're just solving a problem they personally experience in their work. There is an entire mystery cult dedicated to astrological magic, and many magi have an interest in it besides.

  3. Magus is interested in geography. Maybe he's read Ptolemy as described in the chapter in Ancient Magic, maybe he sails a lot and wants to navigate better, or maybe it's just an academic interest. Accurate timekeeping allows for calculating longitude with precision otherwise impossible, so in this case the clock is a means to an end. This is the same development that lead to marine chronometers historically, just a lot earlier. I could see house Mercere having this idea.


Would all magi realise this? No, for the reasons mentioned. Is it plausible that some magi with certain interests could realise it? Very, imo.

Agreed, but in a way that's my point. Most magi wouldn't realise it, and the few that would seem appealing to us precisely because we are modern people - like our characters aren't.

It seems reasonable to us, in the 21st C, that people would want to calculate longitude with precision, would create the equivalent of the 19th C village clock to sit prominently in their covenant, and (pursuing the "what might House Mercere want" line) we could imagine that House Mercere might create a kind of standardised time like 19th C railway companies. None of that makes a game exploring a Mythic version of the medieval world more interesting - it just gives us a way to make the world less medieval.

Personally, I love exploring Mythic versions of the middle ages. But if I wanted magical chronometers and precision and devices that pushed society towards the 19th C, I'd play a steampunk game. (Not that I have a problem with that - I still have fond memories of Castle Falkenstein, for example - that just isn't what I want from Ars Magica.) Hence my comment about "I'm not sure it adds much to the saga".

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Realistically most magi would realize it, but in a sort of abstract "oh hey, yeah, if I wanted to put the effort into developing this I could." sort of way rather than seeing a practical application.

But that's the bit I don't agree with. Timekeeping, and the inaccuracy of timekeeping methods available, was a problem people in the 13th century were aware of and actively working on improving. And as soon as a better technology came along, right at the end of the century, it was immediately adopted with great enthusiasm.

I think it fits right in to a mythic version of the late middle ages - because the invention and adoption of mechanical clocks happens in that period with or without magic anyway. So the story of "new, more precise timekeeping device becomes available" is period appropriate, the only difference is that the magic one is better but restricted to magi. There are works dealing with the design of timekeeping devices from just before the start of an Ars saga (like Ibn al-Sa'ati's "On the Construction of Clocks and their Use" C. 1203) and ones during the period of the game (which are not themselves extant, but Robertus Anglicus writes in 1271 that his contemporaries were actively pursuing methods of creating entirely mechanical clocks).

I'd argue that a "mythic version of the middle ages" that ignores that is actually the less true to life portrayal, and it undersells the thriving intellectual activity of the period. It is a matter of preference in the end, of course, but in my opinion if you're not using things like this as fuel for stories you're missing out on some really great ones.


And of all the many problems, that's useful to focus on?

I don't disagree with any of your points. But it was a trivial problem that very few people cared about, and IMO it doesn't improve sagas to dwell on something that does nothing but move us prematurely towards the modern era. I get that this is a personal taste thing. And I get that I (still remembering the wonder of first discovering the old 2nd edition, loving the details and folk beliefs of the middle ages, and half-seriously considering running my next Ars saga using the Over the Edge rules :wink: ) am hopelessly out of step with where Ars Magica fandom has gone in the last couple of decades. But I'll still make a plea for letting the wonder of the period shine through, rather than trying to usher in a different period.

It might be my lack of knowledge talking, but I'm seriously struggling to see this. Why would inaccurate time be a problem for the average person, or even the average academic? Can you give a few practical examples?

To clarify my thinking a bit, I understand how big timekeeping is. Specially for us in modern times. But I agree with Kevin, we constructed our life around it (for good reasons!) in so many ways that are not even apparent in our day to day. Part of this usefulness, however, hinges on other advancements (for example, one of the main drivers of precise clocks was navigation).

In medieval times the Church was pushing for it, sure... but that is pretty much it. I can't really see how precise measurements of hours change anything for the average medieval, just as the Easter Computus doesn't really have any practical impact in someone's life, and precise measurement of weight is only a marginal gain for the average person unless you have very precise interests (I'm looking at you, alchemists) and a lot of other things to take advantage of that precision.

So yeah, I agree that a magus can pretty much devise a device to give someone a perfect measure of time. But I also share the opinion that this alone also seems to be pretty much useless, and the reasons that make accurate timekeeping desirable won't be around for a few more centuries.

But again, this might be a flawed understanding due to lack of knowledge.

But it is part of the period? And it's quite wonderful! The 13th-14th century is arguably the most important period in the history of horology. Clocks were very much not a trivial or minor thing either - they were important enough that clock towers were being build despite the huge expense and limited accuracy of the existing technologies.

At the start of an Ars saga a massively expensive water clock tower has just been added to the Great Mosque of Damascus, and another is being built in Baghdad. It's just a few decades away from the explosion of tower clocks across western and central Europe. The hourglass is revolutionising ocean navigation. It's the very period where our modern ideas of timekeeping start to take form.

It might be my lack of knowledge talking, but I'm seriously struggling to see this. Why would inaccurate time be a problem for the average person, or even the average academic? Can you give a few practical examples?

@RafaelB it's a reasonable question and really comes in two parts. First, and intuitive to us, is the simple need to know what time it is. People in the 13th century used all sorts of methods to tell what time of the day it was for exactly the same day-to-day reasons we do now. They used water clocks, solar clocks, candle clocks, the hours of prayer (more on that in a bit) and so on. But all of these were unreliable to varying degrees. Imagine going about your daily routine, except every timekeeping device you have (which are not abundant) can be off by anywhere up to several hours in the worst case. Or imagine trying to organise a public event in such an environment. This annoyed people then as much as it would annoy us.

There is actual a line of thought that this period is the birthplace of our modern sense of personal time caused by the invention of more accurate clocks. The opposite can also be argued - that a rising desire for punctuality in urban environments created the incentive to push timekeeping technology forward. Either way, the increase in productivity this leads to, as a simple product of being able to schedule people accurately and en masse, is not to be underestimated.

The second part is not as intuitive to us, but in this period the hours of prayer were of vital importance in the minds of many members of society (especially the clergy). In both the Christian and Muslim worlds there was a strict ordering of the day in terms of what prayers were to be said and at what time. A lot of effort was put into keeping that straight and this is why so many early clock towers are associated with mosques and churches. Even outside the religious angle these canonical hours and the Muslim equivalent were used by normal people to divide up the day.

Less relevant to the average person are the use in astronomy/astrology. You can do a lot here with measurements and calculations but that is a whole lot of work. Ideally, you want something which can track the hard-to-calculate celestial motions at least partially automatically. The core of which has to be a very accurate mechanical clock. This eventually leads to astronomical clocks, but not until the 15th-16th century. However, we know from some of the earliest mentions of mechanical clocks as a concept (such as by Robertus Anglicus) in the mid-late 13th century that this was an idea which a number of academics were already aware of and were actively working towards. It would just take a long time to bring to fruition in the end. Considering magi are part of that same intellectual milieu, I'd be surprised if no one tried their hand at it out of curiosity if nothing else.

It's also really hard to navigate out of sight of land without accurate timekeeping. By the 13th century hourglasses and stellar calculations are being used to great effect for this purpose. Still, it's far from perfect and navigational errors caused by inaccuracies in this method of timekeeping are not uncommon and sometimes fatal. Navigators were fully aware of this problem but the technology for compact and stable mechanical clocks simply wasn't there yet.

edit: Also the astrology one is of unique interest to magi because horoscopes are sympathetic connections, so making them easier to compute has obvious benefits.


Thanks for the explanation @Argentius, it was very insightful!

Rereading the discussion, there doesn't seem to be any fundamental disagreeing in everyone opinions. I'll voice a few more considerations.

First, I'll disagree with the argument of anachronism raised by a few based on:

  1. The fact that, as explained by Argentius, it isn't anachronic;
  2. We accept magic used to create stoves and automatic brooms, ambient heating and lighting, music devices, precise and fast manufacture (I really hate Craft magic, by the way)... but not timekeeping?

The key point of contention is: "how important timekeeping really was"? And for me the answer still is "important, but that depends both on what is your trade and how widespread precise timekeeping is".

We need to recognize that for magi it is, indeed, important. And important enough to give origin to a mystery cult around it (and who is to say that the coleagues of Robertus Anglicus weren't magi researching timekeeping? :thinking:). I'd even say that while astrology itself is old, the mystery of Hermetic Astrology is very likely to have originated only in the last few decades.

However the key advantages of precise timekeeping aren't much, RAW, unless you have the astrological virtues from TM:RE. Specially, magically knowing the astrological time seems to be explicitly useless to calculate horoscopes, which would be the most interesting usage to your everyday magus (on the other hand, we could simply assume that it is already part of calculating an horoscope, and this is why hermetic horoscopes work).

For the medieval population in general, timekeeping will bring changes in the next few decades and centuries, but this won't be perceptible for some time yet. Also, I doubt that the Order is going to enchant clocks and other devices to measure time and spread them around Europe, so we won't be seeing these changes brought forward "before the right time" (wink wink).

It's possible that some magi will put a clock in their covenant? Yes. Likely even. Will this have any practical relevance? Not much. Maybe this can account for some modifier on the covenfolk productivity, just as any other magical device. Magi can probably find a few more uses for one. But until the usage of clocks is widespread, benefits will still be marginal (what is the point of having the precise hour if the local church, the merchants, the city, the king don't have?).

A few magi with ships will probably realize that clocks are useful for navigation, and might think of constructing one. But at the same time, with the several other available magical effects, it doesn't seem much to write home about.

As for the Church, we will still be praying in unholy hours for a few decades, and this is also hardly going to change before the right time (the Quaesitors will make sure that no one sells a clock to a priest (and now I have an idea for a story, thanks!!)).

Overall, I am still of the opinion that while clocks are a big deal, hermetic clocks alone have limited usefulness.

A few thoughts
1st, yes moe accurate timekeeping was an intense subject of the day. Like many areas of advancement today it was something of intense interest to a few people which found widespread application once the principles were discovered and the technology developed.

2nd, magic would provide a shortcut, a way for those with an interest to gain a far mre accurate style of timekeeping much more quickly. Any system which tries to maintain historical reality while introducing magic will rapidly develop these kinds of anachronisms.

3rd) given the limited ability to reproduce magical solution, a magical solution would actually suppress research into more mundane solutions while not being able to become as widespread as a more mundane solution has the potential to be. As such I believe the magical solution would actually help to maintain a prolonged medieval period of lower technology, by undercutting the demand for accurate mundane clocks.

I totally agree, and I am going to be totally obnoxious about it.
In what way would such endeavours make a good roleplayable story?

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Publically available time keeping (like big clocks) enables the amazing technology that is.... scheduling and the appointment.

People will now be able to see if they're going to be on time for church, and if they have time to anything else first. You can arrange meetings with people by getting them to meet when the clock is pointing to two, and then have somebody else turn up when the clock points to three, as opposed to "come by my workplace and I'll talk to you when I have the time."

Having played in many LARP games where people don't have their modern timepieces with them, lack of timekeeping can really make business and politics hard.


True, but what they miss is not accurate timekeeping but a common reference time. People may agree to meet after mass, or when the priest calls for prayer, or when the church bells ring, or at dawn or sunset, or when the tavern keeper has the stew ready. Whether the authoritative timing is accurate matters only to those who travel from out of earshot, and even then only major inaccuracies are likely to matter.

Accurate timekeeping is a serious abstraction which takes a serious switch of mindset to get used to. Even if you manage to invent the device, it will take a generation or two to train even your covenfolk to use it. But maybe that's exactly where we have a roleplayable story.

And obviously it is a similarly major leap for the LARPers to do without their modern devices.


Or, it makes business and politics different. That's kind of the point I've been trying to make (badly, it seems).

Modern people assume that accurate time keeping is useful, because it is useful for us in the way we live our lives. So, yup, if you try to get people at a LARP to abandon their time pieces then yes, they struggle - they are used to organising their lives a different way. LARPers often try to sneak a peak at a clock (e.g. on a phone) because it is so central to how we live today. And then in tabletop RPGs they assume that their characters will want to know what the time is, too.

Objectively, of course there are benefits. But those benefits fundamentally change the way that people organise their lives, understand time, establish contracts, schedule their work, etc. Personally, I'd rather introduce elements into the game that help the players enjoy the medievalness of it, rather than introducing elements which drag the characters out of the middle ages towards the modern period.

Sure, Craft Magic is another excellent example of something that is theoretically logical, but isn't necessarily good for sagas / for the setting. Dropping a bit of magically-powered industrial revolution
into a saga could be really interesting as a twist for a novel saga (i.e., interesting if the PCs do it), but basically breaks the setting if it is seen as a part of the setting (i.e. destructive if anyone else does it).

As a storyguide running Ars Magica, IMO one of the fundamental tensions that one has to navigate is that the setting is absolutely wonderful, inspiring, full of amazing potential... but is essentially broken. (And the more 5th ed supplements have made emphatic statements and added rules, and the more they've tried to paper over the broken bits with more complicated broken bits, the worse this has got.) As a storyguide this tension is actually wonderful - it is a source of creative stimulation. But we also have to guard against breaking things further. Seeing all the supplements as more like the pirate's code (guidelines and suggestions, not rules), and then imagining ways in which people and powers in the setting will adapt and respond to those potentials and tensions, makes great stories.

But I guess what I'm circling around here, is that personally, I want those to be stories to feel like medieval stories - not modern (or industrial revolution) stories. Which is why magic timekeeping, Craft magic, etc. are things I'll happily hand-wave away, ignore, or work around.

To take those examples - "create stoves and automatic brooms, ambient heating and lighting, music devices, precise and fast manufacture" and magic timekeeping - try this an an exercise: If you found a newly-discovered, long-lost book/chronicle by someone like Walter Map, which of those might you plausibly find there?

It feels like a genuine 12th/13thC writer could plausibly have written that someone has a cauldron that cooks food for them, or that in a certain house the faeries/demons/magic does the housework, or that someone has a magic harp that plays itself, or that a certain "noble's" hall has the wonderful property of never being cold. ... But it doesn't feel likely that they would have written about how a certain town had built factories, or that such-and-such a person organised his life with a glorified pocket-watch - that feels more like Charles Dickens.

So, what do we do with Ars Magica, where the rules are so wonderfully broad and flexible that we could do anything we want with magic? The answer, I think, is (1) to try to escape our natural desire to use it to do things which are familiar to us (modern), while making the imaginative effort instead to do things which feel less modern, and (2) work around or hand-wave away things which, however logical or consistent, are destructive to the setting.

Because that is how we get to more things that give us good answers to loke's question...


I wouldn't call it obnoxious, it was asked before and I did kind of ignore it in my last comment (because it was already getting way too long).

Some ideas:

  • The nearby monastery (by which the locals order their day - a common feature of many communities at this time) gets angry that the magus has undermined their control over timekeeping. Does the magus give up his pet project for the sake of peace, or do they battle with the monks for control?
  • The new clock allows the covenant to organise themselves much more efficiently. Visitors to the covenant remark on this, and soon a host of magi are writing to them demanding they sell the lab texts or wanting to commission a clock of their own. This offers great opportunity, but there is no way to satisfy all these new "patrons", and some are quite powerful...
  • The new clock allows the covenant to organise themselves much more efficiently. Visitors to the covenant remark on this, and soon a fine clock becomes a must have item for any self-respecting covenant. This begins a wave of competition across the hermetic world, with covenants competing to have the most impressive and advanced clocks to prove their superiority over their rivals.
  • Magical clocks become so lucrative that many craft-inclined magi start to focus on them at the expense of their usual endeavours. Magi across Europe find that their go-to item makers are now entirely occupied with clocks and this turns their ire on the fools who started the craze!
  • A local merchant sees the magical clock and is taken with the idea. He convinces the burghers of his town to try and commission one from the magi. Is placing a large magical device in full public view wise, or even permitted by the code? And if other towns in the region all start to demand clocks, will the covenant be able to keep up?
  • An enterprising (and open minded) bishop hears about the clock and asks the covenant to produce one for his cathedral. Creating a magical device which will operate under an intense dominion aura is no mean feat. Do the magi rise to the challenge, or refuse and risk offending the bishop?
  • A magus interested in navigation hears of the clock, and proposes that with such accurate timekeeping it should be possible to traverse the deep oceans with unparalleled precision. He proposes an expedition to [farthest Africa/Thule/Hyperborea/into the Atlantic/the purple isles/Hy-Brasil etc.] and wants to recruit the inventor of the clock as a collaborator.
  • A magus equipped with a portable clock notices something odd - time in many magical regiones seems to flow at slightly different rates than the mundane world. The discrepancy is so small it would never have been noticed without the clock. What is the cause of this phenomenon? Might it be related to the idea that the deep magic realm is somehow connected to time itself? Or are the phenomena on which magical durations are based influenced by the regio somehow?
  • Now that the magi have accurate clocks they can time their schedules down to the diameter. How do the covenfolk react to this sudden focus on punctuality? Do they take to it with relish, or will the cries of "you're late!" cause rising animosity between grog and master?
  • The idea of precision clocks begins to filter out into hermetic society. While the direct impact is moderate, many magi begin to contemplate the nature of time and spell durations. Correspondence begins to circulate which speculates about the possibility of spells which can have precise durations rather than the momentary/diameter/sun/moon intervals of current hermetic theory. Of course, the opinion these magi are most interested in is that of the inventor of the clocks, who has gained a certain reputation in this nascent field.
  • As clocks begin to proliferate and people's conception of time starts to change (at least within hermetic society) house Merenita begins to notice with some alarm that this is having a ripple effect on the faerie realm, which appears to be focused on the origin point of the concept - the player covenant! What strange influence will this have on local faeries?
  • A lab accident while making a magical precision clock seems to be doing something strange to the covenant aura. Meanwhile, mundanes in the surrounding region seem to suddenly be more aware of time and increasingly frustrated at the limited timekeeping devices currently available. Could the lab accident have caused some macrocosmic change in the magic realm which is influencing the region?