Car Philosophy 101

Dear Car Talk

Dear Car Talk | Oct 01, 1990

Dear Tom and Ray:

I have a couple of questions that have bothered me for a long time. First, why does the side view mirror on the passenger side of the car make things look so far away? Second, why do your emergency flashers stop flashing when you step on the brakes?

TOM: Hal, it's obvious that you're a philosopher. Only philosophers have time to ponder such profound issues. In fact, we have letters asking these same questions from Aristotle, Plato, Kant, Goethe...and now Hal!

RAY: Anyway, Hal, the reason the brake lights override the emergency flashers on most American cars is that they both share the same filament on the same bulb. Since they are both, in effect, the same light, the designers had to make a choice. Which one should take precedence? They opted for the brake lights.

RAY: The theory is that if you're having car trouble, and you're driving with your flashers on, the drivers behind you still want to know when you're stopping. If they don't, you may find yourself with even more car trouble before long! We should point out we don't think this is a very smart design. And neither do the Europeans or Japanese, both of whom require that the turn signals and flashers be completely separate from the brake lights; also, they require that the flashers and directionals be amber colored (orange) to further differentiate them from the brakes.

TOM: The reason the passenger side mirror makes things look smaller is that it's slightly convex. That means it's curved outward. While it makes things look smaller, it also allows you to see more of what's back there. The wider view let's you see the traditional passenger side "blind spot," so that you don't change lanes and accidentally run over a Ford Festiva.

Get the Car Talk Newsletter