The proving ground is where new theories and equipment are tested.

The theory of relativity revolutionized our understanding of space and time.

Marxism is a political and economic theory developed by Karl Marx.

Scientists often use hypothetical scenarios to test their theories.

Copernican theory revolutionized our understanding of the solar system.

Structuralism is a theory that focuses on the underlying structures of language and culture.

The econ class focuses on studying economic theories and principles.

The Big Bang Theory is a scientific explanation for the origin of the universe.

The scientist presented factual evidence to support his theory.

Freudian theories have greatly influenced the field of psychology.