However, when the musical notation within the painting was analysed, it was found to be the work of Thomas Crecquillon circa 1549. Crecquillon was a composer from the Netherlands, who was active after Bosch's death.
An ink drawing of seven characters emerging from an egg to sing by Bosch exists and is held in Berlin, so experts have now concluded that Concert in the Egg, while clearly using Bosch's style and preparatory drawing, was completed by someone else. As a result, the work has now been attributed to an "anonymous follower of Bosch".
The original painting is an oil on panel dating from around 1561. It is a fascinating piece with numerous details, quirky ideas, humour and comments about life at that time. Ten singers emerge from the egg, possibly the yoke suggesting that they are yokels or "fools".
They are engaged in singing, following Thomas Crecquillon's score and oblivious to everything that is happening around them and the dangers lurking there.
The artist seems to have depicted people representing all aspects of the village population, from the nun with the owl on her head, to what some experts have suggested is a foolish philosopher wearing glasses and a funnel on his head, rich, old, men, women.
Although they are all supposed to be singing from the same sheet of music, the singers' expressions and positions suggest that the outcome would not be a pleasant sound! Taking a look around the egg, many of Bosch's familiar symbols and items are used, particularly the birds and food.
The viewer is able to spot some of the dangers surrounding the group. For instance, breaking through the egg near the creature playing the lute, a thief is cutting the purse strings from the man pointing to the music.
Just below that, a hand breaks out through the shell and tries to reach the grilled fish, which a cat is also watching carefully. To the left of this, fire burns through a village.
Either side of the singers, bare and withered branches rise from the egg. On the right, the branches support a basket of cooked food that the scavenging birds are about to eat and on the left, a snake hangs from a branch. Some have suggested that this is an eel and play on the word ale.
Concert in the Egg is a fascinating image which will continue to tease and tantalise the viewer for years to come with its puzzling assortment of characters and symbols.