商品经济是以交换为目的的经济形式,而契约是人与人之间某种交换关系的外化。它使得一切基于血缘、宗教、伦理、权力而形成的人对人的依赖关系退居到了次要地位乃至于被完全粉碎,从而使平等主体得以自由参与交易活动,自负责任,自担风险。对此,英国法学家梅因爵士用“从身份到契约”作了精辟的概括。法的精神是法律制度的灵魂,契约自由则被视为现代法精神的内核,它在整个 The commodity economy is an economic form for the purpose of exchange, and the contract is the externalization of a certain exchange relationship between people. It enables all people based on kinship, religion, ethics and power to relegate people’s dependency on people to their subordinates or even to be completely shattered so that equal subjects can freely participate in the trading activities themselves, at their own risk. In this regard, the British jurist Sir Maine made an incisive summary of “From Identity to Contract ”. The spirit of law is the soul of the legal system and the freedom of contract is regarded as the core of the spirit of modern law.