Use 'base upon' when something factual supports a belief, idea, or narrative.

Fact Foundation

'Base upon' indicates a story is inspired by real events, not entirely fictional.

Storytelling Root

When using 'base upon', your statement should stand on solid, indisputable ground.

Use 'base upon' to show that a personal viewpoint stems from specific information or belief.

Highlight that an opinion may not be reliable if 'based upon' unverified info or gossip.