There is no contradiction between the two statements of relativity principle.

相对性原理的经典表述中并无矛盾。

youdao

This paper presents two basic principles: 1. Relativity principle of minimum force;

提出二个基本原理：1。相对性最小作用力原理；

youdao

The relativity principle of a contract was a major principle in classical laws for contracts.

合同的相对性是古典契约法上的重要原则。

youdao

Assuming this principle (without proving it) allowed Einstein to develop the general theory of relativity in 1916, and to describe gravity in purely geometric terms.

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