Research methods for criminology and well as early theories have had little if no change to those of today.

One early theory is that a small amount of cesium-137 might have found its way into the roadbed when it was built in 1963.

Locke is also responsible for an early theory of personal identity.

Cabanis did not think that these results were out of harmony with his earlier theory.

But some of his early theories are no longer considered heretical.

Recent studies have demonstrated his long lasting impact on early modern medical theory.

He developed early theories about the medieval warm period and little ice age.

An earlier theory was that the word meant "temple of the sun".

In past space accident investigations, early theories often proved wrong.

But if you want to know where those earlier theories came from, I'd have to recount five thousand years of scientific history.