# Paradigm Shifts 3: With a Vengence

The last shift I wanted to present is best explained at http://tauday.com/ . There you will find a manifesto (yes, a manifesto) about why we should change from using $$\pi = \text{180 degrees}$$ as the circle constant to $$\tau = 2 \pi = \text{360 degrees}$$ It’s quite a convincing argument, and it’s a shift that can easily be made. Check the website for more. TAU VS PI