Learn from history to make decisions for the future.
One hopes Sonny Bill Williams can look over his shoulder into the past before he decides on what to do next.
Williams has been a walking band-aid this season, lurching from one injury to the next.
It is fair to say his rate of return for New Zealand Rugby this season is akin to a poor performing bonus bond.
But all is not lost for Williams, and he only has to look back to the last man to regularly wear the No 12 jersey for the All Blacks to realise it could be blue skies ahead.
The first thing Williams should do is jump on the plane and come back to New Zealand.
Williams has played in just five tests this season and was a rare sight for the Blues in Super Rugby, just one of many in that outfit which picked up injuries.
The former Bulldogs star is now 33, and as we all know, time waits for no man. He has been hit with wrist, shoulder and knee injuries this year and then a bout of illness.
Williams has been playing top level sport for 15 years now, having made his debut for the Bulldogs when he was still a teenager. Maybe it is all catching up with him.
But perhaps all Williams needs is to look at what happened to Ma'a Nonu in 2014.
Nonu broke his arm in mid-September of that year, and that put him out of all rugby for the rest of the season. He missed the end of the year tour to the northern hemisphere.
Nonu gave his body a break and had some time away from the game.
He came back the next year fit and firing.
That was when Nonu actually had a decent season of Super Rugby - he helped the Hurricanes make it all the way to the final, where they were beaten by the Highlanders.
He then pushed on to the World Cup and was one of the best in black when the All Blacks beat Australia in the final at Twickenham.
Nonu's good form was put down to the ability to have a full pre-season. He gave his body the time to recover from the rigour of a full season, and then got properly match-fit.
Perhaps that is the way Williams should head - forget about the meaningless game against Italy, and come back here and get the body and mind some rest and recuperation.
Get rid of all those niggles in and start afresh when Super Rugby kicks off in mid February.
But unfortunately for Williams, that is not going to happen. His Mickey-Mouse boxing career is going to get in the way as he shapes up against reality television star Stu Laundy - no, never heard of him either - on December 1.
It is for charity, but for Williams charity starts at home.
Williams needs to give this fight a miss and put all his energies into getting his body and mind right for next season.
If he does, he could leave the black jersey as a world champion.
