I prefer the ancient Greek scholar--Thales of Miletus, I think--who said just 4 words: "Moderation in all things."
If we lived in moderation--following the main course, rather than allowing the pendulum to swing to extremes--we would be better off.
One passage in The Bible says that, too--in Proverbs?--but I haven't been able to find it again, perhaps due to various translations and editions. It speaks about turning neither to the right hand nor to the left.