It's a radical theory, even for someone like me who has long ago been forced to become determinedly openminded, to abandon scepticism and prejudice.

The contradictions have been so confusing that a rather radical theory has been emerging with a small portion of believers for their friendship.

After the radical theory was established, the interest in the toxic substance with the awful smell decreased.

The theory was ultimately challenged and made redundant by radical theory.

The period between 1880 and 1920 was particularly fertile for radical theories, a fact many contemporary scholars stubbornly or stupidly ignore, and most of the theories weren't even new then.