"Fool (If You Think It's Over)" is the title of a popular song originally publicly released in 1978 by the British singer-songwriter Chris Rea. Rea also wrote the words and composed the music of the song, which appears on his 1978 debut album, Whatever Happened to Benny Santini?. The single's charting success in the USA earned him a Grammy nomination as Best New Artist in 1979.

Who sang fool if you think it over? Let's have some stream of consciousness first.
The relevant information to answer the above question is: "Fool (If You Think It's Over)" is the title of a popular song originally publicly released in 1978 by the British singer-songwriter Chris Rea. So, the answer is the British singer - songwriter Chris Rea.