How can you tell if your favorite celebrities have that special Irish spirit flowing through their veins? The following clues will help you deduce celebrities’ IQ (Irish Quotient!). Please note: No special equipment is required, except maybe a pint of Guinness — just to help your concentration!

Gift of the Gab

It’s scientifically proven that the Blarney Stone works miracles. At least, that’s what a little guy in a green lab coat told us! None are better speechmakers and storytellers than the Irish. So, are any of your favorite celebrities as expressive as Frank McCourt? Or by chance, do their remarks echo the cracklin’ wit of your Irish granny? These stars show that a “grand turn o’ phrase” could have Irish origins:

Kathy Griffin — this wise-cracking comedian teases the heck out of her ever-patient Irish mother and mom’s tendency to tipple on box wine. This feisty redhead has cousins in counties Kerry and Louth. We wonder if Kathy’s folks had to flee the auld sod after dissing someone’s Aran sweater with a punchy Gaelic put-down?

Martin Sheen — is acclaimed for his powerful real-life speeches as a political activist, as well as his presidential oratory on The West Wing. Of Irish and Spanish stock; both sides of Sheen’s family fought oppression in their war-tossed homelands before coming to America.

Jimmy Fallon — with his genial patter, the Tonight Show host truly can talk up a storm. Many jokes riff on his Irish traits such as a painful struggle to tan. A recent genealogical survey showed Fallon’s ancestry to be about 4/5 Irish. The other 1/5 apparently had a thing for “those Irish eyes.”

A Fondness for the Good Times

Now some Irish may prefer sitting by the fire with a cup of tea. However, Erin’s own can shake up any shindig.

Jack Nicholson — famously declared “I’m Irish, I think about death all the time”—this might explain Jack’s mission to have barrels of fun in this life. Plus, his infamous “top of the morning to ya” grin is full of legendary (and lucky) charm.

Lindsay Lohan — this freckled lass is a big fan of leppin’ around the dance floor. Maybe hunting leprechauns till dawn might come from father Michael Lohan, born on the shores of Galway Bay.

Rihanna — This sultry songstress with a taste for nightlife shenanigans hails from Barbados. Her father has African ancestry as well as roots among the Barbadian “red-legs.” This community is descended from Irish rebels, enslaved for defying the English.

Plain, Decent Folk

Apart from talking a mile a minute and jigging till sunrise, the Irish are also a “no airs and graces” nation. They take a dim view of forgetting your childhood friends or playing “king of the castle.” These no-nonsense stars typify the practical nature of the Emerald Isle.

Liam Neeson — the Antrim native was no star-struck dreamer as a child. His first foray into drama was to get close to a lovely Irish girl—at the tender age of 11. Such a romantic little fella, our Liam! On his way to Hollywood, he worked at a Guinness brewery and tried out as professional soccer player—so he’s no stranger to the rough and tumble. Despite many awards, Neeson has an unaffected demeanor that endears him to fans and other stars alike

Saoirse Ronan — despite shooting to stardom at a young, impressionable age, Dublin-reared Saoirse keeps her low-key Irish ways. Although blessed with stunning beauty, Ms. Ronan doesn’t blink in the flashbulbs’ glare. The plain-spoken young lady states “the events and the glamorous side doesn’t faze me.” Although this lass will go far, it’s a fair bet that she’ll keep her feet firmly on the ground.

Colin Farrell — once associated with bad-boy ways, Farrell has recently reconnected with his Dublin roots, staying in close touch with his family there. Although he’s had many leading roles, as the Irish would put it, “he’s not too full of himself” Farrell’s dad actually runs a homespun healthfood store called “Down to Earth.’

This feature was based on Rasher Tierney’s book F*ck You I’m Irish: Why We Irish Are Awesome. You can follow Rashers on Twitter @effyouimirish, or on Facebook at EffYouImIrish.