Harry Jackson: There was a time when I could run all day without breaking a sweat. I tell ya: it's hell getting old.
[while running up a stairwell with his son]
MacGyver: Age is only in the mind, Harry.
Harry Jackson: Well, my mind tells me I'm gettin' old.
MacGyver: When I was about ten I got my first chemistry set. I've been a beaker and test-tube nut ever since. My mom said I was gonna come up with a formula that would either improve the world... or blow up the house.
Harry Jackson: Hey, bud; where in the Sam Hill are you goin'?
[Macgyver has a flash back]
Young MacGyver: Dad, who's Sam Hill?
MacGyver's Father: You've been talking to your Grandpa Harry again?
Young MacGyver: Yeah. Who's Sam Hill?