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.
ユークリッド幾何学は五つの公準に基づいている。
Euclidean geometry is based on five postulates.
この理論では
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.