I don’t know what edition of the Philosopher’s Stone you have but perhaps you recognise that wizard at the top there. That’s the chap who adorned the back cover of the Original Philosopher’s Stone, little 9 year old me thought it was just a bad drawing of Dumbledore, my sister thought it was supposed to be Quirrell. I’ve also heard Fudge (presumably because of those pinstripe trousers) or Nicholas Flamel. The truth is rather more mundane, he was just a random wizard. According to Thomas Taylor, the illustrator, he just painted a eccentric looking wizard character It was actually based on his father. When the books became popular and fans started wondering who the wizard could be he was replaced with a drawing of Dumbledore. Anyway now I have the Dumbledore edition (my orginal Philosopher’s Stone got burnt by my mother ‘cos she thought it was satanic) I find I rather miss the anonymous wizard, he has a very lively look in his eye which combined with the book he is holding promises a good story.