postulate
A fundamental assumption accepted without proof, used as a basis for reasoning in mathematics, logic, or formal systems. Similar to an axiom but often used in specific contexts like Euclidean geometry or logical systems.
Euclidean geometry is based on five postulates.
In this theory, we proceed with the discussion based on several postulates.
From 公 (public, official) and 準 (standard, rule). The term was coined in Japanese to translate the Western concept of 'postulate' in mathematics and logic.