Much has been written about keeping one's mind active, and that such will (might) defer mental weakness in old age. Many people do puzzles such as crosswords or sudoki. What do you have after doing a puzzle? Nothing.
Here is a better way to exercise your mind: Learn Ancient Greek. Here's how to do it. A very fine, enjoyable book aptly titled, Learn Ancient Greek, will help you. The book was written by Peter Jones [ISBN 0-7156-2758-9] and it WILL help you learn to read and translate the ancient Greek language in which Socrates, Aeschylus, Sophocles and even the New Testament was written.
I know - I have finished 17 out of 20 chapters, with the last three mostly more translation exercises. The selections are from Antigone, Plato and the Gospel of John. Peter Jones teaches basic pronunciation, grammar and the common words. He focuses on reading and recognizing the usage of a word, which he presumes you will use a dictionary to find the meaning of its stem. His lessons have humor and are practical.
Once you know the basics, you can find great texts in Ancient Greek from the Loeb Classics Library of Harvard University Press for $24 each, including the translation in English on the opposite pages. Also, the Cambridge University courses for more study of Ancient Greek are available on Amazon, including CD recording on its pronunciation.
Put that puzzle down and Learn Ancient Greek!
Word of the Day
"Scaramouche" - noun [$10] a Mencken word.
Scaramouche means a character of the Italian theatrical form known as commedia dell'arte: an unscrupulous and unreliable servant. His affinity for intrigue often lands him in difficult situations but he always manages to extricate himself, leaving an innocent bystander as his victim.
Sentence: The debt ceiling 'talks' participants all seem to be scaramouches with the plain people - Joe & Jane Average, as their victims.