Thomas Erastus was a doctor who lived in Switzerland in the 1500s. He believed that people should not be punished for their beliefs, and instead believed that all people have the right to practice whatever religion they wanted. He also believed in treating everyone fairly and equally, regardless of their backgrounds. Erastus set up a system which encouraged people to pay for any medical services they received, and he was an early pioneer of the idea of healthcare insurance. His work was very influential, and today we still use a lot of principles he introduced. He is remembered as a groundbreaking thinker who believed in helping all people, no matter what their beliefs were.