On one of the last shows, Alex tried to talk his dumb friend out of joining the Marines. The friend “Boner” explained that he wasn't smart, like Alex. Alex could do anything but he was so dumb that the Marines was his best choice.
The narrow mindedness of liberals shouldn't surprise me anymore...
I think you may be combining Family Ties and Growing Pains.
Me thinks you are mixing together a couple of different shows.
But your point is still valid and correct.