Heckscher-Ohlin Theorem: Crucial Two-Factor Assumption

The Heckscher-Ohlin (H-O) theorem explains international trade patterns based on differences in national factor endowments. It posits that countries export goods whose production relies heavily on abundant factors and import goods using scarce factors.

Core Assumptions Analysis

The H-O theorem relies on several simplifying assumptions. Evaluating the options provided:

• Two-factor model: This is fundamental. The theorem compares countries based on relative abundance and intensity of use of factors like capital and labor. The core logic hinges on having at least two factors to establish these differences and trade patterns.
• Two commodities: While a common simplification in the basic model, the core principle can be extended to multiple goods. It's less critical than the factor aspect.
• No tariff / Constant tariff: These assumptions simplify the model by removing trade barriers. While important for the basic setup, the fundamental H-O logic about trade driven by factor endowments exists independently of specific tariff levels. The *absence* of barriers is a simplification, not the core explanatory mechanism itself.

Importance of the Two-Factor Assumption

The most critical assumption is the existence of a two-factor model (typically capital and labor). This allows for:

• Differentiating Countries: Countries can be classified based on relative abundance (e.g., capital-abundant vs. labor-abundant).
• Differentiating Goods: Goods can be classified by factor intensity (e.g., capital-intensive vs. labor-intensive).
• Explaining Trade: The theorem's prediction directly links a country's factor abundance to its export patterns, which requires comparing at least two factors. Without this distinction, the basis for comparative advantage described by H-O disappears.

Therefore, the two-factor model assumption is the most important for the Heckscher-Ohlin theorem's core explanation of international trade.