Identify Logical Fallacies

Analyze argument text to detect and explain logical fallacies

Overview

The identifyLogicalFallacies flow analyzes a piece of argument text to identify any logical fallacies present and provides detailed explanations for each detected fallacy.

This flow is used as a standalone tool for fallacy analysis and can be applied to any argument text.

Function Signature

export async function identifyLogicalFallacies(
  input: IdentifyLogicalFallaciesInput
): Promise<IdentifyLogicalFallaciesOutput>

Source: src/ai/flows/identify-logical-fallacies.ts:30

Input Schema

argumentText · string · required

The text of the argument to analyze for logical fallacies.

Input Type

const IdentifyLogicalFallaciesInputSchema = z.object({
  argumentText: z
    .string()
    .describe('The text of the argument to analyze for logical fallacies.'),
});

type IdentifyLogicalFallaciesInput = z.infer<typeof IdentifyLogicalFallaciesInputSchema>;

Output Schema

fallacies · string[] · required

An array of logical fallacies identified in the argument.

explanation · string · required

A detailed explanation of each identified logical fallacy.

Output Type

const IdentifyLogicalFallaciesOutputSchema = z.object({
  fallacies: z
    .array(z.string())
    .describe('An array of logical fallacies identified in the argument.'),
  explanation: z
    .string()
    .describe('A detailed explanation of each identified logical fallacy.'),
});

type IdentifyLogicalFallaciesOutput = z.infer<typeof IdentifyLogicalFallaciesOutputSchema>;

Example Usage

import { identifyLogicalFallacies } from '@/ai/flows/identify-logical-fallacies';

const result = await identifyLogicalFallacies({
  argumentText: `Everyone I know supports this policy, so it must be the right choice. 
  And if you disagree, you're just not smart enough to understand it.`
});

console.log('Detected fallacies:', result.fallacies);
// Output: ['Ad Populum (Bandwagon)', 'Ad Hominem']

console.log('Explanation:', result.explanation);

Common Fallacy Types Detected

The AI is trained to identify various logical fallacies including:

• Ad Hominem: Attacking the person instead of the argument
• Straw Man: Misrepresenting an opponent’s position
• False Dichotomy: Presenting only two options when more exist
• Appeal to Authority: Using authority as the sole basis for truth
• Slippery Slope: Claiming one action will lead to extreme consequences
• Circular Reasoning: Using the conclusion as a premise
• Hasty Generalization: Drawing conclusions from insufficient evidence
• Red Herring: Introducing irrelevant information to distract
• And many more…

Implementation Details

The flow uses a specialized AI prompt that:

1. Analyzes the argument text for logical errors
2. Identifies specific fallacy types present
3. Explains why each instance constitutes a fallacy
4. Returns structured output with fallacy names and explanations

Prompt Template (from src/ai/flows/identify-logical-fallacies.ts:40):

You are an expert in logical fallacies. Your task is to identify any logical 
fallacies present in the given argument text and provide a detailed explanation 
for each fallacy.

Argument Text: {argumentText}

Identify the fallacies and provide explanations:

Related

• Explain Logical Fallacy Flow
• Fallacy Detection Schema
• Generate Blueprint Flow - includes fallacy detection