Assumption
/əˈsəm(p)SH(ə)n/
ʟᴏɢɪᴄᴀʟ
: a basic or foundational belief that is the basis for other beliefs
// presuppositions, properly basic beliefs, ultimate authorities
All reasoning begins with assumptions (acknowledged or not). We have basic and foundational beliefs that ground all of our other beliefs.
Beliefs based on perception, reason, introspection, memory, intuition, testimony, sensus divinitatus
Beliefs based on trusted experts
Beliefs about God, time, history, nature, etc.
A Worldview typically has one or more foundational assumptions.