Tuesday, March 30, 2010

Logic and Rules: Part 1

So, more and more I see people putting “I feel that…” into conversations regarding the rules of this game. An example of which is the INAT FAQ, where the organizers change and make up rules to suit themselves. If you don’t believe me, look at their Tyranid section, then how they go around to define weapons as “hull-mounted” when the codex does not, the difference being a huge change in line of sight of the weapon. So I am here today to lay some ground rules to go by when assessing whether or not something is supported by the rules. To begin this multi-segmented article, I will show the four basic gates of logic, as well as their relevant truth tables. Ambiguity cannot be tolerated, for logic necessitates absolutes; all terms that people consider ambiguous will be defined for the purposes of examples.

For those unfamiliar with binary, 1 means true, 0 means false.

Generally, A and B will be used for examples.

AND- defined as * symbol

00 = 0

01 = 0

10 = 0

11 = 1

Essentially, this gate boils down to that both sides of the symbol must be true in order for the sentence as a whole to be true. For it to be true I had a burger and a drink (A*B), I really do have to have a burger and a drink, for it is false otherwise.

OR- defined as “v” for our purposes

00 = 0

01 = 1

10 = 1

11 = 1

An OR gate claims that at least one of the pieces are true. I have either a quarter or lint in my pocket (AvB). Turns out that I had lint, but it is still true.

IF- THEN - defined as >, or Wakka Wakka Man

00 = 1

01 = 1

10 = 0

11 = 1

This is the trickiest of them thus far, for it states that we do not have A true and B false. If I eat a burger, then I will get fat (A>B).

IF AND ONLY IF- Well, for simplicity’s sake, we’ll just use +

00 = 1

01 = 0

10 = 0

11 = 1

This gate states that it is true only in the case that both parts are either both true or false. I am awesome if and only if I can prove it. (A + B)

For the purposes of “not”, ~ will be our requisite symbol.

For the conclusion I will use “#” as the symbol

The import:

OK, now that I’ve done all this, what the hell is the use?

Unlocking language, in a sense.

Let’s look at Pedro Kantor’s Chapter Tactics rule to start:

If you include Pedro Kantor, then your guys exchange Combat Tactics for Stubborn and your Sternguard gain the Hold the Line! Special rule.

So, how does this reduce to logic?

If Pedro, then Stubborn and Hold the Line! (P > S * H)

Yet, players have stated that you can combine Vulkan and Pedro to form the Wonder Twins!

If Vulkan, then Awesome (not going to write all the rules) (V > A)

Continuing on, the rules state that if you have more than one character, then you must choose which of their Chapter Tactics will be used. This reduced in to logic in this fashion: It is not the case that if you take Pedro and Vulkan that you gain both Chapter Tactics.

~( P * V)

Say I take Pedro and Vulkan, and wish to cheat by saying that I can use the TL-awesome rule and Hold the Line! Can an argument be made for this:

If I take Pedro and Vulkan, then I can have both TL-awesome, and Hold the Line

I have Pedro

I have Vulkan

Therefore, I gain TL-awesome and HtL

(P * V > A * H)



# A * H

Why, this only shows that any twit can get away by not reading all the rules! Let’s look at the real way in which this works:

(P > S * H)

(V > A)

~(P * V)

At this point, we must affirm one, or deny the other to get any result at all!

I want Vulkan!


# A

The key is that it is true that I took Vulkan, and therefore it is true that I gain TL-awesome

Now, there were some things I did in here that I will be covering next time in my quest for the Holy Grail of rules lawyering, and these are called the Simplification and Inference rules!

If there are any questions, send me an email at dominobi@gmail.com


  1. All of this could have been summed up in the words "If you have more than one character who replaces Combat Tactics in the army, the player must choose which one he will be taking." As it does in the Space Marine codex...

    People just need to read the rest of Pedro's Chapter Tactics to realize that the "Hold the Line" rule in bold near the bottom of his entry is not simply a stand alone rule, but rather it is defining what it does since it isn't defined in the Chapter Tactics section of his rules.

    Dom uses a very logical way to go a long way around the barn on this one, but it works.

  2. You do have a good specific example, loki, but Ishmael's post is only using the example to illustrate the application of a general process. If you can remember his notes and gates, then you can apply the process to more than one example and use it to solve multiple rules questions.

  3. I am aware, but all people really have to do is RTFM. Simply put, there are a lot of rules, and there are 2 major problems when it comes to rules in this game.

    1. So many rules that it is easy to forget, confuse, or make mistakes given the large number and...

    2. Knowing and finding out which rules take president over others in given situations.

    I don't want to discount what Dom says. The Emperor knows he much wiser than I, especially in this area. But I caution the use of complex logic systems in a game that is already full of rules questions :D.

  4. This is a good way too look at a lot of the issues plaguing 40k right now and in the case where everything is spelled out nice and neatly in the rules it works. But I agree with Loki on this one Especially with the above stated scenario. The answer is already spelled out in the rules. But these lines of logic at least tend to break down when the rules aren't worded as clearly. (Ie some of the rules questions in the Tyranid codex)