Square the circle

To square the circle is to attempt something extremely difficult if not impossible and dates in this sense from the 1600s. Constructing a square equal in area to a circle has obsessed mathematicians since Babylonian times. Over many millennia, mathematicians got very close to solving the problem but it was only in the late 19th century that it was proven to be mathematically impossible. It is too complex a problem to explain here but those who wish to know more details can find them at https://en.wikipedia.org/wiki/Squaring_the_circle