The NYRB edition of The Life of Henry Brulard - the old Penguin edition as well - ends with a separate 1840 document called "The Privileges". It begins "May GOD grant me the following letters patent:", and continues with a list of what we would now call super-powers. Some samples:
"ARTICLE 4:... The privilege-holder having a ring on his finger and squeezing that ring when looking at a woman, she will become passionately in love with him as we believe Héloïse was with Abelard.
ARTICLE 5: Good hair, excellent teeth, good skin never grazed. Faint, pleasing smell.
ARTICLE 10: When out shooting, eight times a year, a small flag will indicate to the privilege-holder, at a distance on one league, the game that exists and its exact position.
ARTICLE 16: The privilege-holder, wherever he may be, having said: 'I ask for my food,' will find: two pounds of bread, a beefsteak well done, a leg of lamb idem, a bottle of Saint-Julien, a carafe of water, one item of fruit, an ice-cream and a demi-tasse of coffee. This request will be answered twice in twenty-four hours."
Etc. Small sums of money, minimal physical pain, prowess in combat, the ability to turn into an animal. This is a strange piece of writing. I should point out that Stendhal wrote this when he was fifty-seven years old.
Nota Bene, in a comment, reasonably suggested that one could use Stendhal's memoirs to illuminate some of the more (some of the many!) perplexing aspects of his fictional characters. There are no shortage of parallels between young Henri Beyle and the fictional Julien Sorel and Fabrizio. But I'm having enough trouble understanding Stendhal himself (or "Stendhal"). Henry Brulard is a slippery book. I'll have to refer Nigel to Erich Auerbach's chapter on Stendhal in Mimesis and puzzle on the subject some more.