Over time, even facts we consider steadfast truths can change. People used to think doctors could forgo washing their hands before surgery. Knowledge is ever-evolving.

The seven ideas below probably changed since your school days. Re-educate yourself.

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THEN: Pluto is a planet

NOW: Pluto isn’t a planet

We’ve known since the late 1800s that a ninth planet, after Uranus, potentially existed. In 1906, Percival Lowell, the founder of the Lowell Observatory in Flagstaff, Arizona, even began a research project intended to locate the mysterious read more >>>

Source:: BusinessInsider.Com