Common Sense
Depends on the your experience and local weather.
Before I got my IMC rating I once flew under a load of 500' cloud but over the sea (less aerials) and vis was OK and weather at Southend was cavok.
Locally I don't mind doing circuits with a 1000' cloud base but why take a risk doing any more. IMC is a good skill but the scenery sucks once you can't see the wing tips and if you don't have an IMC or IR then its just a silly way to die.
Stay in the hangar and relax and live to fly another day.