Principle that in a disagreement everyone will abide by the decision of most of the people?

The principle you’re referring to is known as "majority rule." This democratic concept asserts that in a disagreement or decision-making process, the choice that receives the most votes or support from the group will be accepted by all members, regardless of their individual preferences. Majority rule is foundational in various governance systems, ensuring that decisions reflect the will of the greater number while also promoting fairness and collective responsibility. However, it is essential to balance this principle with protections for minority rights to prevent potential tyranny of the majority.