He's testing if you can think in binary. Label the bottles of wine with binary numbers, 0000001 to 1100100. Give the first mouse every other bottle of wine, the second mouse every bottle of wine with a 1 in the 2's place, the second mouse every bottle with a 1 in the 4's place, etc. If a mouse dies, the poison lies in one of the bottles it was given. If a mouse survives, there is no poison in any of the bottles it was given. Since every combination of mice is associated with a unique bottle, you can read off the digits formed by the dead and live mice to determine which bottle it was.

And then hope none of your guests call the SPCA.