Sub-argument:

(1) Science depends on the development needs of technology (economic relations).

(2) The economic base determines the superstructure, and the superstructure reacts on the economic base.

(3) Historical contingency is determined by economic inevitability.

Demonstration method of demonstration application:

Argument 1:

Here, examples are used to prove that the development of science is often due to the need of technology. Hydrostatics and self-study are used respectively. In other words, it proves that the need of economic relations is the decisive foundation of scientific development.

Sub-argument 2: This passage is demonstrated by examples.

This paper compares "economic relationship" to "red line" and emphasizes its rise through metaphor. It plays a decisive role, intuitive, appropriate and vivid.

Sub-argument 3: Use two examples and a metaphor to demonstrate.

Demonstrate with examples. Citing the example of Napoleon, the military dictator, Marx found the example of historical materialism, which shows that Thierry, Miner and others have made efforts in this regard. Even without Marx, historical materialism will be found. Moreover, Morgan discovered historical materialism in America. This further proves that the appearance of great men is accidental and the appearance of such people is inevitable.

Metaphorical argument is used here, comparing contingency to "curve" and inevitability to "the central axis of curve". The curve always swings up and down around the central axis, which makes contingency always show the truth of inevitability, and it is clear and intuitive.