The thinker from the Scientific Revolution who first proposed a heliocentric theory, where the Earth revolves around the Sun, was Nicolaus Copernicus.

While others had proposed the idea before, Copernicus was the first to develop a comprehensive and mathematically sound model for the heliocentric system in his book "De Revolutionibus Orbium Coelestium" (On the Revolutions of the Heavenly Spheres), published in 1543.

It's important to note that his theory was initially met with resistance and controversy, as it challenged the prevailing geocentric model (Earth-centered) which had been accepted for centuries.