TRADECRAFT: The Intelligence Analyst’s Guide to the Internet

TRADECRAFT: Propositional Logic (The Code of Truth)

The Concept

Most people think they are “Logical.” They are usually just “Rationalizing.”

True Logic is a system of rules, just like Math. If you break the rules of Math (2 + 2 = 5), you are wrong. If you break the rules of Logic, you are wrong, no matter how “right” you feel.

We are going to learn the most common logical structure in human language: The Conditional Statement.

If P, then Q.

P is the Antecedent (The Cause).
Q is the Consequent (The Result).

Example:

If it is raining (P), Then the ground is wet (Q).

THE TRAP: Affirming the Consequent

This is the #1 Logic Error in politics and media.

It works like this:

Rule: If it is Raining (P) → The Ground is Wet (Q).
Observation: The Ground is Wet (Q).
False Conclusion: Therefore, it is Raining (P).

Why is this false?

Because the ground could be wet for a hundred other reasons (A sprinkler, a spilled drink, a flood). Just because you see the Result (Q), you cannot prove the Cause (P).

Real-World Example (The Political Smear):

Rule: If you are a Terrorist (P) → You criticize the Government (Q).
Observation: You are criticizing the Government (Q).
False Conclusion: Therefore, you are a Terrorist (P).

This is formally called Affirming the Consequent. It is a logical fallacy. It is not an “opinion”; it is a mathematical error.

TRADECRAFT TOOL: The Truth Table

A cheat sheet for spotting broken logic.

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Explore

Logic Structure	Name	Validity	Example
If P then Q. P happens.	Modus Ponens	✅ VALID	“It is raining. Therefore ground is wet.”
If P then Q. Not Q.	Modus Tollens	✅ VALID	“Ground is NOT wet. Therefore it is NOT raining.”
If P then Q. Q happens.	Affirming Consequent	❌ INVALID	“Ground is wet. Therefore it rained.” (Maybe it was a hose?)
If P then Q. Not P.	Denying Antecedent	❌ INVALID	“It isn’t raining. Therefore ground isn’t wet.” (Maybe a hose?)

LAB EXERCISE: The “Headline Translation”

Convert these headlines into Logic Equations (P → Q) to see if they hold up.

Drill 1: The Health Scare

Headline: “Everyone who died of the new virus ate carrots!”
The Logic: If you die of virus (P) → You ate carrots (Q).
The Error: You found a dead person who ate carrots (Q). Does that mean the carrots killed them? No. (Affirming the Consequent).

Drill 2: The “Gateway Drug” Argument

Argument: “Every heroin addict started with milk. Therefore, milk causes heroin addiction.”
The Logic: If Heroin Addict (P) → Drank Milk (Q).
The Error: Just because Q is true for all P, does not mean Q causes P.

Drill 3: The “Success” Cult

Argument: “Bill Gates dropped out of college. Therefore, to be a billionaire, you should drop out.”
The Logic: If Bill Gates (P) → Dropout (Q).
The Error: Affirming the Consequent. Most dropouts (Q) are not Bill Gates (P).

ACTION ITEM: The “If-Then” Filter

For the next 24 hours, every time you hear an argument, try to rephrase it in your head as:

“If [P], then [Q].”

Check the direction of the arrow. Are they driving down the wrong side of the road?