I know (believe me, I know) that it sometimes seems as if it’s difficult to change direction in life, and perhaps that’s a reflection of our tendency to say the phrase I did a total 360 instead of the correct statement I did a total 180.

The statement is based on the fact that there are 360 degrees in a complete circle, so if we’re using the analogy of the circle to talk about change, 180 degrees indicates the greatest possible change. If you pick a point as zero on your circle (that is, your starting point) and draw a line from there to the farthest point opposite there, it is 180 degrees of the circle. In other words, to go 180 degrees is to go as far as possible opposite your starting point.

To go 360 degrees is to come full circle, ending up exactly where you started. That’s how the phrase I did a complete 180 came to signify a complete change, as in I did a complete 180 about exercise. That person may have gone from being Susie the Spud (Couch Potato) to Suzanne the Non-stop Swimming Machine. If she had done a complete 360, then you’d have needed to pass the gravy to Susie the Spud since she’d have been right back on the couch, with remote control, hot-buttered popcorn, and back-to-back-to-back reality television shows.

It’s easy enough to confuse since, for many of us, it’s been a long time since high school geometry class, but if we want to change, we might as well start with getting the phrase right.

–Paul

Paul’s book–Literally, the Best Language Book Ever;

Sherry’s Grammar List