Epicureanism....Rationalism?

Could epicureanism have been the start of the modern day rationalism? I say this due to the fact that Epicureanism held the belief in "atomness". When someone says atomness, it triggers a scientific chord in my mind. Now maybe the Romans did not mean for atomness to refer to science but I sure think they did. They were an advancing society and who knows what those philosophers and thinkers were conjuring up after sitting in the libraries, immersed in their studies. Another reason I think epicureanism might be a precursor to rationalism is due to the fact that they thought people had their own free will. This idea of free will does not seem to be very prominent in ancient cultures and even some cultures after the BC, but the epicureans were an example of a culture based on free will. This idea seems very modern because a lot of people nowadays believe in the idea of free will. I believe epicureanism laid the foundation to modern day rationalism, and even if it didn't it certainly seems like a very modern set beliefs held by the Romans.