The phrase "absolute fool" is used to describe someone who is extremely foolish or lacking intelligence without any doubt or exception. Full definition
And yet they insist on investing like absolute fools. (marketwatch.com)
The biggest kick in this down - and - dirty escapade is the willingness of some pretty big names — Bob Costas, Al Michaels, Ernest Borgnine, Robert Vaughn and Robert Stack among them — to make absolute fools of themselves in small parts. (sfgate.com)