Divination - Caidan's theorem

A Practical Discussion (PGTS)
1

Hi ! I’m new to this series of books, and this far I love it :slight_smile:

I’ve seen something a bit weird in the glossary : Caidan’s theorem, that dictates how much thaum/s are needed to keep a divination spell up, depending on base cost and distance. In the glossary, the formula given is B x distance/100^(B/100) with distance expressed in meters and B the base cost.

This formula is very strange, because written like this, it means the 100^(B/100) part is the denominator. The consequence is that if you increase B too much, the total cost will start to drop !

Examples :

If the distance is 12 000 meters and the base cost is 100 thaum, the total cost will be 12 000 thaum/s (this value corresponds to what Dryden calculated in Chapter 17 book 2)

However with the same distance and a base cost of 150 thaum, the total cost will be 1800 thaum/s (In the book, these conditions were said to cost over 100 000 thaum/s)

-> I think there is an issue in the formula given in the glossary, it was probably meant to be

[I’ve edited the formula, thanks to Keid]

B * ((distance/100)^(B/100))

PS : Maybe I like maths a bit too much and I should listen to more of Pecanty’s lectures, but I couldn’t help it, I needed to check the maths. The fact it is so precise and science-based is precisely the reason I love these books so much !

2 Likes
2

I’m pretty sure the actual intended formula was B * ((distance/100)^(B/100)). I’m not able to sit down and look at the examples in the books too closely right now, but it seems to work fine for all of your examples (though, “over” 100k thaums is quite a bit over.)

3

Indeed you’re right ! This formula does work with all 3 examples given in the book, I’ll update my first message.

Thanks !