Identify the twins and cousins!

Let me tell you about four friends of mine. They're a close-knit bunch: two pairs of twins who are cousins to each other.

The first guy is Adam. He's a devout Christian, going to church every week. He loves his job and commutes many miles to work each day. He has a very positive outlook, always looking on the bright side. He's content with his life, saying he has some of everything.

His sister is Sukey. She's very different from Adam, although they love each other dearly. She's a pessimist with a gloomy outlook. She's always ready to criticise and make remarks against people she doesn't like. She's practical and generally wants to know what she can take away from a lesson or a situation.

Their first cousin is Matt. He has loads of kids and will soon have a whole swarm of grandchildren. He's a watchmaker by trade, so he's always got the times of day for you. He's almost as fond of Adam's children as his own, and loves distributing sweets to them. His favourite food is pie, and he can't get enough of it: he often has steak and kidney pie for dinner and then apple and blackberry pie for dessert.

His sister is Debbie. She strongly resembles Sukey, but has grown her hair longer and wears it in pigtails. She has a tendency to cause arguments - not intentionally; people just start squabbling when she's around. She makes a hobby of fencing, and spends her free time slashing with a rapier. She loves sandwiches, and likes to vary the type of bread even more than the filling.

Who are these people, and what's their favourite form of entertainment?

• Apart from that CodeNewbie solved it soo quickly, the puzzle is very nice and pleasant to think about. My beloved kind of puzzles. Cheers! – Marek Oleszczuk Jul 3 '15 at 7:11

The twins and cousins are

The four basic mathematical operations
Adam $\rightarrow$ Addition, Sukey $\rightarrow$ Subtraction, Matt $\rightarrow$ Multiplication, Debbie $\rightarrow$ Division

He's a devout Christian, going to church every week.

The plus sign(+) looks similar to the Christian cross($\dagger$).

...commutes many miles to work each day.

Addition is a commutative operation. That is, 2+5 is the same as 5+2.

He has a very positive outlook.

Plus before numbers denotes that they are positive.

...he has some of everything.

A play on the word 'sum'.

Subtraction gives you the difference between numbers.

She's a pessimist...

Subtraction is a negative operation.

She's always ready to criticise and make remarks against people she doesn't like.

These are generally considered negative traits.

...generally wants to know what she can take away...

In subtraction, you take something away from the original.

He has loads of kids and will soon have a whole swarm of grandchildren.

Repeated multiplication can lead to very large numbers. Humans multiply by having kids and those kid further multiply to have grandchildren.

He's almost as fond of Adam's children as his own, and loves distributing sweets to them.

Multiplication is a distributive operation distributive over addition. That is, 5x(3+4) is same as 5x3 + 5x4.

...he's always got the times of day for you.

5 multiplied by 2 can also be said as 5 times 2.

His favourite food is pie...

To find the area and perimeter of a circle, we have to multiply with pi. The multiplication of numbers can be represented using the capital letter pi.

She strongly resembles Sukey, but has grown her hair longer and wears it in pigtails.

The division symbol ($\div$) looks like the minus sign (-), with two dots i.e the pigtails.

... people just start squabbling when she's around.

It helps to divide. Similar to dividing people by creating fights.

...spends her free time slashing with a rapier.

Division can also be represented with a slash, like 15/3. The slash looks like a sword held in the hand during combat.

She loves sandwiches, and likes to vary the type of bread even more than the filling.

When dividing, numbers can be written in the fractional form, with the numerator and denominator changing while the line denoting division remains the same.

Their favourite form of entertainment is

being weapons of math instruction! (Judging by rand's love of Doctor Who, I'd say these are names of Doctor Who actors/characters, and so) they enjoy playing doctor and performing operations. With a little help from rand al'thor, their favourite form of entertainment is opera (which is inspired from the word operations, which they all are.)

• Damn, you're too fast! What gave it away? – Rand al'Thor Jul 2 '15 at 19:31
• Since you were so fast, I won't accept this answer until you explain every clue :-) Each sentence contains exactly one clue. The "favourite form of entertainment" is a jokey bonus which you haven't got yet... – Rand al'Thor Jul 2 '15 at 19:36
• CodeNewbie is on a roll today! – Mark N Jul 2 '15 at 19:40
• @MarkN CodeNewbie is on a roll, full stop. He's been rep-capping nearly every day since he joined! – Rand al'Thor Jul 2 '15 at 19:41
• @randal'thor: [Operations] -> {Opera}? – CodeNewbie Jul 7 '15 at 11:26