Milking the bull

Milking the bull is a proverb which uses the metaphor of milking a bull to indicate that an activity would be fruitless or futile.

In the 16th century, the German painter Hans Schäufelein illustrated the proverb on the eight of bells in a deck of playing cards.

Dr Johnson used the proverb to criticise the work of David Hume and other sceptical philosophers.