Once you work that out you are long way to deciding whether you are in the camp of one of the hottest favourites in the history of the great race or are going to go shopping for value somewhere.
But be warned, if you are in the latter camp you will need whichever horse you are backing to do something special because Incentivise might actually be a champion.
Might. He will need to win tomorrow and add a few more group ones to the trophy cabinet before he starts getting written into racing's book of legends but he is also probably the only horse in today's race with even the opportunity to get there.
Notwithstanding defending champion Twilight Payment, who returns today carrying 58kgs and if we was to win would become a Melbourne Cup legend but whose overall career record might take champion status off the table.
It isn't for Incentivise.
Since remerging from the back blocks of Queensland like some long legged racing monster in the last 12 months he has done what monsters do: scared everything in sight.
He was remarkable over the Queensland winter but staying form there is rarely the ticket to greatness but then he changed stables to Peter Moody, himself one of racing's magic stories of the last year, and has arrived in Melbourne like an equine steamroller.
Incentivise won a A$1million race he shouldn't have been able to win in the Makybe Diva (1600m) and then another one on the Turnbull over 2000m, both against elite fields at distances short of his best.
That confirmed Incentivise was the real deal but what he did in the Caulfield Cup last start was next level should be legally compulsory viewing for anybody considering betting against him today.
From a bad draw and after a hard run on a track probably tighter than he liked he destroyed his rivals and it is impossible to logically back any horse who finished behind him in that race to beat him today.
Today will be tougher though. Mainly because the Europeans weren't at Caulfield and a few of them are there today, with Twilight Payment joined by perhaps an even better UK stayer in Spanish Mission.
Twilight Payment's credentials need no embellishment so his key equation is one of weight and there is a very good reason the No.1 saddle cloth in rarely seen in the winner's circle after the Melbourne Cup in recent decades.
There will be an army of fans who hate taking short odds looking for a horse to back to beat Incentivise and Spanish Mission would have been their poster boy had it not been for failing not one but two veterinary exams late last week.
He has been cleared to start and vet exams can be finicky procedures not linked to a horse's form, wellbeing or even subsequent performance but going into one of the hardest 3200m races in the world it all hardly boosts the confidence.
There are plenty of lightweight contenders, many with European blood and little form reference, who could find themselves being the horse who picks the right day to have their day and upset the big boys.
And Kiwis, whether owned or trained, like Verry Elleegant, The Chosen One and Ocean Billy will attract parochial money. All can finish top 5, maybe the mare can win.
But if you want to back the Melbourne Cup winner today there is no doubt your best chance of doing that is backing Incentivise on just about every metric you could think of.
So then what is a fair price? What makes him a sensible bet instead of just deciding to take a boxed trifecta using your birth date and hoping for a miracle?
Incentivise was as short as $2.30 when the field was released on Saturday but was $2.80 last night and while bookies might be loathe to take too big a stand against him so many once-a-year punters bet on the Melbourne Cup simply for the chance to yell at the television it can skew the tote odds away from logic.
If it does and you can get north of $3 for Incentivise, then it all makes sense.
If not, you always have the birth date back up strategy and if you get beaten you probably got beat by a champion.