Thales Day

Celebrate critical thinking and the transition from myth to logic by getting involved with Thales Day! Raise a glass to the beginning of sound human reasoning by joining in with various activities and events in honor of Thales of Miletus, honoring his life, and learning more about his work that led to modern thinking. 

History of Thales Day

While it might seem impossible to pinpoint the exact day that rational thinking began, some scientists and philosophers believe that it can be traced back to May 28, 585 BC. This is that date most commonly associated with the first accurate prediction of a solar eclipse by legendary Greek philosopher Thales of Miletus. His work is considered to be the common origin of the logical study of nature – the beginning of using reason and sound judgment to better understand the world.

The celebration of Thales Day has taken place unofficially in pockets of the scientific world for many years. In 2015, the event was marked as the 2600th anniversary of science and Danish philosopher, Henrick Schoneberg, was a catalyst for the celebration of the day. Live events took place in Copenhagen and other celebrations also took place in honor of Thales Day in places around the world, including the Chicago Science Fest in the United States.

Since then, Thales Day has become an annual event that acts as a cultural landmark to show appreciation for science, philosophy and critical thinking about nature, with live events in Denmark as well as online and in person activities for those celebrating around the world.

How to Celebrate Thales Day

Scientists, philosophers and thinkers can join in on the fun of celebrating this “father of Western science” with some activities for Thales Day, such as these:

Host an Event for Thales Day

One of the best ways to go about observing and raising awareness for Thales Day might be to host an event in the local community. Whether at a school, university, or science society, the organizers of Thales Day are inviting people all over the world to get involved by enabling constructive dialogue and pursuing human flourishing through mutual understanding. Find more information at the official website for the day.