In simple terms...
Say that during a high speed cruise, the angle of attack of the wing is 3 degrees (hypothetical figures of course) and that the wing stalls at 18 degrees. In order to reach the 18 degree stall AoA will require 6 x the force of gravity (18/3 = 6)....i.e. you will need to multiply AoA x 6 to get 18 degrees.
Now assume you're cruising slowly, and your AoA is 9 degrees. In order to stall the wing will require 2g (18/9 = 2) and so the wing will stall before exceeding the design limitations.....i.e you need to multiply AoA by 2 to reach 18 degrees.
Now assume you're cruising fast but you've added a few more people. This means you'll require a larger AoA to maintain level flight. If now at a high speed cruise with 4 fatties onboard the AoA is 9 degrees, it'll only require 2g to stall the wing......(2x9=18).....
And so on....