Let's make this birthday one to remember.

91 years old (Born on February 04, 1934)

Happy Birthday, Jean-Claude! May your reaction times to cake and champagne remain impressively swift, and may all your decisions today be delightfully irrational—just this once. Your groundbreaking work in mathematical psychology has certainly set the bar high; after all, who else could elegantly bridge philosophy of science with decision theory without breaking a sweat?

Your pioneering Knowledge Space Theory continues to inspire countless learners through ALEKS software worldwide. Here's hoping that on this special day you find yourself comfortably navigating the knowledge space between Belgian chocolates and birthday celebrations.

Cheers to another year filled with brilliant insights—and perhaps fewer equations at parties!