Follow your curiosity

What discovery has been shared with you?

FACTREE gives you something interesting to discover every day — and something worth talking about together.

Start with one fact. Explore it, go deeper, then follow whichever branch catches your imagination.

Choose subjects for a surprise

Exploring any topic

Begin your discovery

Your next discovery is one click away.

Choose one or more subjects above, or leave Any Topic selected and let curiosity decide.

Philosophy

The Problem of Induction and Scientific Knowledge

Quick fact

The Scottish philosopher David Hume identified this problem in the 18th century, arguing that our belief in cause-and-effect is based on habit, not reason—a challenge that still unsettles scientists and philosophers today.

Why this is interesting

Every time you drop a ball, it falls to the ground. But what if, on the very next drop, it floated upward? How could you prove it won't?