0:00:12.536,0:00:13.510
Thank you very much.

0:00:13.510,0:00:16.084
So, yes, I'm Hannah Fry,[br]I am a mathematician,[br]

0:00:16.084,0:00:20.403
and today I want to talk to you[br]about the mathematics of love.

0:00:20.941,0:00:22.681
Now, I think that we can all agree

0:00:22.681,0:00:27.098
that mathematicians[br]are famously excellent at finding love.

0:00:27.597,0:00:31.045
But it's not just[br]because of our dashing personalities,

0:00:31.045,0:00:35.102
superior conversational skills[br]and excellent pencil cases.

0:00:35.544,0:00:40.070
It's also because we've actually done[br]an awful lot of work into the maths

0:00:40.070,0:00:42.462
of how to find the perfect partner.

0:00:42.462,0:00:45.875
Now, in my favorite paper[br]on the subject, which is entitled,

0:00:45.875,0:00:49.371
"Why I Don't Have a Girlfriend" -[br](Laughter) -

0:00:49.371,0:00:53.091
Peter Backus tries to rate[br]his chances of finding love.

0:00:53.091,0:00:55.457
Now, Peter's not a very greedy man.

0:00:55.457,0:00:57.542
Of all of the available women in the U.K.,

0:00:57.542,0:01:00.955
all Peter's looking for[br]is somebody who lives near him,

0:01:00.955,0:01:02.856
somebody in the right age range,

0:01:02.856,0:01:05.480
somebody with a university degree,

0:01:05.935,0:01:08.304
somebody he's likely to get on well with,

0:01:08.304,0:01:10.440
somebody who's likely to be attractive,

0:01:10.440,0:01:12.838
somebody who's likely[br]to find him attractive.

0:01:12.838,0:01:15.441
(Laughter)

0:01:16.128,0:01:20.239
And comes up with an estimate[br]of 26 women in the whole of the UK.

0:01:21.441,0:01:23.602
It's not looking very good, is it Peter?

0:01:23.602,0:01:26.119
Now, just to put that into perspective,

0:01:26.119,0:01:29.444
that's about 400 times fewer[br]than the best estimates

0:01:29.444,0:01:32.799
of how many intelligent[br]extraterrestrial life forms there are.

0:01:33.439,0:01:37.676
And it also gives Peter[br]a 1 in 285,000 chance

0:01:37.676,0:01:40.536
of bumping into any one[br]of these special ladies

0:01:40.536,0:01:42.131
on a given night out.

0:01:42.131,0:01:44.171
I'd like to think[br]that's why mathematicians

0:01:44.171,0:01:46.915
don't really bother[br]going on nights out anymore.

0:01:47.332,0:01:49.164
The thing is that I personally

0:01:49.164,0:01:51.753
don't subscribe[br]to such a pessimistic view.

0:01:51.753,0:01:54.342
Because I know,[br]just as well as all of you do,

0:01:54.342,0:01:56.714
that love doesn't really work like that.

0:01:56.714,0:02:01.304
Human emotion isn't neatly ordered[br]and rational and easily predictable.

0:02:01.872,0:02:04.401
But I also know that that doesn't mean

0:02:04.401,0:02:07.485
that mathematics hasn't got something[br]that it can offer us

0:02:07.488,0:02:10.966
because, love, as with most of life,[br]is full of patterns

0:02:10.966,0:02:15.042
and mathematics is, ultimately,[br]all about the study of patterns.

0:02:15.749,0:02:19.925
Patterns from predicting the weather[br]to the fluctuations in the stock market,

0:02:19.925,0:02:23.230
to the movement of the planets[br]or the growth of cities.

0:02:23.230,0:02:25.784
And if we're being honest,[br]none of those things

0:02:25.784,0:02:29.500
are exactly neatly ordered[br]and easily predictable, either.

0:02:29.500,0:02:34.647
Because I believe that mathematics[br]is so powerful that it has the potential

0:02:34.658,0:02:38.101
to offer us a new way of looking[br]at almost anything.

0:02:38.101,0:02:41.187
Even something as mysterious as love.

0:02:41.470,0:02:43.525
And so, to try to persuade you

0:02:43.525,0:02:48.036
of how totally amazing, excellent[br]and relevant mathematics is,

0:02:48.036,0:02:53.826
I want to give you my top three[br]mathematically verifiable tips for love.

0:02:57.290,0:02:59.238
Okay, so Top Tip #1:

0:03:01.488,0:03:03.811
How to win at online dating.

0:03:06.290,0:03:09.593
So my favorite online dating website[br]is OkCupid,

0:03:09.593,0:03:13.224
not least because it was started[br]by a group of mathematicians.

0:03:13.224,0:03:15.289
Now, because they're mathematicians,

0:03:15.289,0:03:16.723
they have been collecting data

0:03:16.723,0:03:19.937
on everybody who uses their site[br]for almost a decade.

0:03:19.937,0:03:22.118
And they've been trying[br]to search for patterns

0:03:22.118,0:03:24.040
in the way that we talk about ourselves

0:03:24.040,0:03:26.102
and the way that we interact[br]with each other

0:03:26.102,0:03:27.538
on an online dating website.

0:03:27.538,0:03:30.448
And they've come up with some[br]seriously interesting findings.

0:03:30.448,0:03:32.136
But my particular favorite

0:03:32.136,0:03:35.271
is that it turns out[br]that on an online dating website,

0:03:35.271,0:03:40.480
how attractive you are[br]does not dictate how popular you are,

0:03:40.825,0:03:44.343
and actually, having people think[br]that you're ugly

0:03:44.343,0:03:46.803
can work to your advantage.

0:03:48.220,0:03:49.898
Let me show you how this works.

0:03:49.898,0:03:53.703
In a thankfully voluntary[br]section of OkCupid,

0:03:54.124,0:03:57.467
you are allowed to rate[br]how attractive you think people are

0:03:57.467,0:03:59.157
on a scale between 1 and 5.

0:03:59.157,0:04:02.901
Now, if we compare this score,[br]the average score,

0:04:02.901,0:04:05.786
to how many messages[br]a selection of people receive,

0:04:05.786,0:04:07.446
you can begin to get a sense

0:04:07.446,0:04:11.344
of how attractiveness links to popularity[br]on an online dating website.

0:04:11.344,0:04:15.160
This is the graph that the OkCupid guy[br]shave come up with.

0:04:15.160,0:04:18.838
And the important thing to notice[br]is that it's not totally true

0:04:18.838,0:04:21.860
that the more attractive you are,[br]the more messages you get.

0:04:21.860,0:04:24.477
OK, there's maybe a bit of a trend there,

0:04:24.477,0:04:27.629
but it's got an R squared[br]of absolutely naff all, let's be honest.

0:04:27.653,0:04:31.784
But the question arises then[br]of what is it about people up here

0:04:32.108,0:04:35.853
who are so much more popular[br]than people down here,

0:04:36.305,0:04:39.166
even though they have the same[br]score of attractiveness?

0:04:39.166,0:04:43.121
And the reason why is that it's not just[br]straight forward looks that are important.

0:04:43.121,0:04:45.922
So let me try to illustrate[br]their findings with an example.

0:04:45.922,0:04:49.662
So if you take someone like[br]Portia de Rossi, for example,

0:04:50.042,0:04:53.799
everybody agrees that Portia de Rossi[br]is a very beautiful woman.

0:04:54.957,0:04:58.555
Nobody thinks that she's ugly,[br]but she's not a supermodel, either.

0:04:58.555,0:05:02.813
If you compare Portia de Rossi[br]to someone like Sarah Jessica Parker,

0:05:05.430,0:05:08.236
now, a lot of people,[br]myself included, I should say,

0:05:08.236,0:05:12.239
think that Sarah Jessica Parker[br]is seriously fabulous

0:05:12.959,0:05:15.310
and possibly one[br]of the most beautiful creatures

0:05:15.310,0:05:18.205
to have ever have walked[br]on the face of the Earth.

0:05:18.205,0:05:21.994
But some other people,[br]i.e., most of the Internet,

0:05:24.822,0:05:28.763
seem to think that she looks[br]a bit like a horse. (Laughter)

0:05:30.142,0:05:33.970
Now, I think that if you ask people[br]how attractive they thought

0:05:33.970,0:05:36.199
Sarah Jessica Parker[br]or Portia de Rossi were,

0:05:36.199,0:05:38.846
and you ask them to give them[br]a score between 1 and 5,

0:05:38.846,0:05:41.999
I reckon that they'd average out[br]to have roughly the same score.

0:05:41.999,0:05:44.780
But the way that people would vote[br]would be very different.

0:05:44.780,0:05:47.370
So Portia's scores would[br]all be clustered around the 4

0:05:47.370,0:05:49.767
because everybody agrees[br]that she's very beautiful,

0:05:49.767,0:05:52.437
whereas Sarah Jessica Parker[br]completely divides opinion.

0:05:52.437,0:05:54.637
There'd be a huge spread in her scores.

0:05:54.637,0:05:57.059
And actually it's this spread that counts.

0:05:57.059,0:05:59.425
It's this spread[br]that makes you more popular

0:05:59.425,0:06:01.717
on an online Internet dating website.

0:06:01.717,0:06:03.303
So what that means then

0:06:03.303,0:06:05.758
is that if some people[br]think that you're attractive,

0:06:05.758,0:06:07.522
you're actually better off

0:06:07.522,0:06:11.462
having some other people think[br]that you're a massive minger.

0:06:12.353,0:06:14.758
That's much better[br]than everybody just thinking

0:06:14.758,0:06:17.065
that you're the cute girl next door.

0:06:17.065,0:06:19.280
Now, I think this begins[br]makes a bit more sense

0:06:19.280,0:06:22.601
when you think in terms of the people[br]who are sending these messages.

0:06:22.601,0:06:24.932
So let's say that you think[br]somebody's attractive,

0:06:24.932,0:06:28.636
but you suspect that other people[br]won't necessarily be that interested.

0:06:28.636,0:06:31.284
That means there's[br]less competition for you

0:06:31.284,0:06:34.142
and it's an extra incentive[br]for you to get in touch.

0:06:34.142,0:06:36.969
Whereas compare that to[br]if you think somebody is attractive

0:06:36.969,0:06:40.187
but you suspect that everybody[br]is going to think they're attractive.

0:06:40.187,0:06:43.565
Well, why would you bother[br]humiliating yourself, let's be honest?

0:06:43.848,0:06:46.064
Here's where the really[br]interesting part comes.

0:06:46.064,0:06:49.954
Because when people choose the pictures[br]that they use on an online dating website,

0:06:49.954,0:06:52.446
they often try to minimize the things

0:06:52.446,0:06:55.576
that they think some people[br]will find unattractive.

0:06:55.576,0:06:59.338
The classic example is people who are,[br]perhaps, a little bit overweight

0:07:00.152,0:07:02.946
deliberately choosing[br]a very cropped photo,

0:07:04.874,0:07:06.932
or bald men, for example,

0:07:06.932,0:07:09.773
deliberately choosing pictures[br]where they're wearing hats.

0:07:09.773,0:07:12.358
But actually this is the opposite[br]of what you should do

0:07:12.358,0:07:13.874
if you want to be successful.

0:07:13.874,0:07:17.840
You should really, instead, play up to[br]whatever it is that makes you different,

0:07:17.840,0:07:22.156
even if you think that some people[br]will find it unattractive.

0:07:22.156,0:07:25.396
Because the people who fancy you[br]are just going to fancy you anyway,

0:07:25.396,0:07:29.965
and the unimportant losers who don't,[br]well, they only play up to your advantage.

0:07:30.867,0:07:34.303
Okay, Top Tip #2:[br]How to pick the perfect partner.

0:07:34.346,0:07:37.350
So let's imagine then[br]that you're a roaring success

0:07:37.350,0:07:39.136
on the dating scene.

0:07:39.136,0:07:43.494
But the question arises of how do you then[br]convert that success

0:07:44.299,0:07:47.310
into longer-term happiness[br]and in particular,

0:07:47.310,0:07:51.202
how do you decide[br]when is the right time to settle down?

0:07:51.202,0:07:54.380
Now generally,[br]it's not advisable to just cash in

0:07:54.380,0:07:56.340
and marry the first person[br]who comes along

0:07:56.340,0:07:58.456
and shows you any interest at all.

0:07:58.456,0:08:01.519
But, equally, you don't really[br]want to leave it too long

0:08:01.519,0:08:04.840
if you want to maximize your chance[br]of long-term happiness.

0:08:04.840,0:08:08.438
As my favorite author,[br]Jane Austen, puts it,

0:08:08.438,0:08:10.800
"An unmarried woman of seven and twenty

0:08:10.800,0:08:14.128
can never hope to feel or inspire[br]affection again."

0:08:14.128,0:08:16.125
(Laughter)

0:08:16.971,0:08:19.861
Thanks a lot, Jane.[br]What do you know about love?

0:08:21.336,0:08:22.835
So the question is then,

0:08:22.835,0:08:25.329
how do you know when[br]is the right time to settle down

0:08:25.329,0:08:28.040
given all the people[br]that you can date in your lifetime?

0:08:28.040,0:08:31.487
Thankfully, there's a rather delicious bit[br]of mathematics that we can use

0:08:31.487,0:08:33.989
to help us out here, called[br]optimal stopping theory.

0:08:34.044,0:08:35.580
So let's imagine then,

0:08:35.580,0:08:37.987
that you start dating when you're 15

0:08:37.987,0:08:41.678
and ideally, you'd like to be married[br]by the time that you're 35.

0:08:42.106,0:08:43.776
And there's a number of people

0:08:43.776,0:08:46.559
that you could potentially[br]date across your lifetime,

0:08:46.559,0:08:49.842
and they'll be at varying levels[br]of goodness.

0:08:49.842,0:08:53.326
Now the rules are that once you cash in[br]and get married,

0:08:53.326,0:08:56.243
you can't look ahead to see[br]what you could have had,

0:08:56.243,0:08:58.728
and equally, you can't go back[br]and change your mind.

0:08:58.728,0:09:00.175
In my experience at least,

0:09:00.175,0:09:03.034
I find that typically people don't[br]much like being recalled

0:09:03.034,0:09:08.000
years after being passed up[br]for somebody else, or that's just me.

0:09:08.799,0:09:11.236
So the math says then[br]that what you should do

0:09:11.236,0:09:14.465
in the first 37 percent[br]of your dating window,

0:09:14.465,0:09:18.358
you should just reject everybody[br]as serious marriage potential.

0:09:18.358,0:09:20.604
(Laughter)

0:09:20.604,0:09:24.101
And then, you should pick[br]the next person that comes along

0:09:24.101,0:09:27.222
that is better than everybody[br]that you've seen before.

0:09:27.222,0:09:28.889
So here's the example.

0:09:28.889,0:09:33.325
Now if you do this, it can be[br]mathematically proven, in fact,

0:09:33.851,0:09:36.404
that this is the best possible way

0:09:36.404,0:09:40.142
of maximizing your chances[br]of finding the perfect partner.

0:09:40.770,0:09:45.108
Now unfortunately, I have to tell you that[br]this method does come with some risks.

0:09:46.062,0:09:49.227
For instance,[br]imagine if your perfect partner

0:09:50.382,0:09:52.846
appeared during your first 37 percent.

0:09:53.403,0:09:56.224
Now, unfortunately,[br]you'd have to reject them.

0:09:56.224,0:09:59.015
(Laughter)

0:09:59.865,0:10:01.845
Now, if you're following the maths,

0:10:01.845,0:10:03.558
I'm afraid no one else comes along

0:10:03.558,0:10:05.694
that's better than anyone[br]you've seen before,

0:10:05.694,0:10:09.476
so you have to go on[br]rejecting everyone and die alone.

0:10:09.476,0:10:12.092
(Laughter)

0:10:12.092,0:10:16.352
Probably surrounded by cats[br]nibbling at your remains.

0:10:17.069,0:10:21.258
Okay, another risk is,[br]let's imagine, instead,

0:10:21.258,0:10:24.508
that the first people that you dated[br]in your first 37 percent

0:10:24.508,0:10:27.875
are just incredibly dull,[br]boring, terrible people.

0:10:28.569,0:10:31.757
Now, that's okay,[br]because you're in your rejection phase -

0:10:32.847,0:10:35.818
that's okay,[br]because you're in your rejection phase,

0:10:35.818,0:10:38.052
so thats fine, you can reject them.

0:10:38.642,0:10:41.499
But then imagine, the next person[br]to come along

0:10:41.499,0:10:44.611
is just marginally less boring,[br]dull and terrible

0:10:46.069,0:10:48.408
than everybody that you've seen before.

0:10:48.408,0:10:52.240
Now, if you are following the maths,[br]I'm afraid you have to marry them

0:10:52.240,0:10:55.721
and end up in a relationship[br]which is, frankly, suboptimal.

0:10:56.030,0:10:57.241
Sorry about that.

0:10:57.241,0:10:59.503
But I do think that there's[br]an opportunity here

0:10:59.503,0:11:02.381
for Hallmark to cash in on[br]and really cater for this market.

0:11:02.381,0:11:04.847
A Valentine's Day card like this.[br](Laughter)

0:11:04.847,0:11:08.456
"My darling husband,[br]you are marginally less terrible

0:11:08.456,0:11:11.328
than the first 37 percent[br]of people I dated."

0:11:13.258,0:11:16.006
It's actually more romantic[br]than I normally manage.

0:11:16.920,0:11:21.120
Okay, so this method doesn't give you[br]a 100 percent success rate,

0:11:21.304,0:11:25.100
but there's no other possible[br]strategy that can do any better.

0:11:25.100,0:11:27.824
And actually, in the wild,[br]there are certain types

0:11:27.824,0:11:31.041
of fish which follow[br]and employ this exact strategy.

0:11:31.041,0:11:33.496
So they reject every possible suitor[br]that turns up

0:11:33.496,0:11:36.625
in the first 37 percent[br]of the mating season,

0:11:36.625,0:11:40.218
and then they pick the next fish[br]that comes along after that window

0:11:40.218,0:11:42.521
that's, I don't know, bigger and burlier

0:11:42.521,0:11:45.210
than all of the fish[br]that they've seen before.

0:11:45.210,0:11:49.915
I also think that subconsciously,[br]humans, we do sort of do this anyway.

0:11:49.915,0:11:52.944
We give ourselves a little bit of time[br]to play the field,

0:11:52.944,0:11:56.415
get a feel for the marketplace[br]or whatever when we're young.

0:11:56.415,0:12:01.296
And then we only start looking seriously[br]at potential marriage candidates

0:12:01.296,0:12:03.325
once we hit our mid-to-late 20s.

0:12:03.325,0:12:06.658
I think this is conclusive proof,[br]if ever it were needed,

0:12:06.658,0:12:10.600
that everybody's brains are prewired[br]to be just a little bit mathematical.

0:12:10.886,0:12:12.969
Okay, so that was Top Tip #2.

0:12:12.969,0:12:16.251
Now, Top Tip #3: How to avoid divorce.

0:12:17.713,0:12:20.765
Okay, so let's imagine then[br]that you picked your perfect partner

0:12:20.765,0:12:23.950
and you're settling into[br]a lifelong relationship with them.

0:12:24.841,0:12:28.595
Now, I like to think that everybody[br]would ideally like to avoid divorce,

0:12:28.595,0:12:32.219
apart from, I don't know,[br]Piers Morgan's wife, maybe?

0:12:34.904,0:12:37.078
But it's a sad fact of modern life

0:12:37.078,0:12:40.422
that 1 in 2 marriages[br]in the States ends in divorce,

0:12:40.422,0:12:43.771
with the rest of the world[br]not being far behind.

0:12:43.989,0:12:46.009
Now, you can be forgiven, perhaps

0:12:46.009,0:12:49.670
for thinking that the arguments[br]that precede a marital breakup

0:12:49.670,0:12:53.436
are not an ideal candidate[br]for mathematical investigation.

0:12:53.436,0:12:55.250
For one thing, it's very hard to know

0:12:55.250,0:12:58.448
what you should be measuring[br]or what you should be quantifying.

0:12:58.448,0:13:04.157
But this didn't stop a psychologist,[br]John Gottman, who did exactly that.

0:13:04.711,0:13:09.559
Gottman observed hundreds of couples[br]having a conversation

0:13:09.676,0:13:12.438
and recorded, well,[br]everything you can think of.

0:13:12.438,0:13:14.850
So he recorded what was said[br]in the conversation,

0:13:14.850,0:13:17.189
he recorded their skin conductivity,

0:13:17.189,0:13:19.034
he recorded their facial expressions,

0:13:19.034,0:13:21.023
their heart rates, their blood pressure,

0:13:21.023,0:13:25.796
basically everything apart from whether[br]or not the wife was actually always right,

0:13:27.257,0:13:29.586
which incidentally she totally is.

0:13:30.608,0:13:33.139
But what Gottman and his team found

0:13:33.139,0:13:36.151
was that one of the most important[br]predictors

0:13:36.151,0:13:38.618
for whether or not a couple[br]is going to get divorced

0:13:38.618,0:13:43.046
was how positive or negative each partner[br]was being in the conversation.

0:13:43.727,0:13:46.113
Now, couples that were very low-risk

0:13:46.113,0:13:50.183
scored a lot more positive points[br]on Gottman's scale than negative.

0:13:50.183,0:13:52.467
Whereas bad relationships,

0:13:52.467,0:13:55.495
by which I mean, probably[br]going to get divorced,

0:13:55.495,0:14:00.023
they found themselves[br]getting into a spiral of negativity.

0:14:00.740,0:14:02.869
Now just by using these very simple ideas,

0:14:02.869,0:14:05.433
Gottman and his group were able to predict

0:14:05.433,0:14:08.148
whether a given couple[br]was going to get divorced

0:14:08.148,0:14:10.684
with a 90 percent accuracy.

0:14:11.137,0:14:14.525
But it wasn't until he teamed up[br]with a mathematician, James Murray,

0:14:14.525,0:14:16.528
that they really started to understand

0:14:16.528,0:14:20.580
what causes these negativity spirals[br]and how they occur.

0:14:20.580,0:14:22.502
And the results that they found

0:14:22.502,0:14:26.200
I think are just incredibly[br]impressively simple and interesting.

0:14:28.267,0:14:29.551
So here they are.

0:14:33.359,0:14:35.480
I think that should be fairly clear.

0:14:36.898,0:14:42.471
So these equations, they predict how[br]the wife or husband is going to respond

0:14:43.396,0:14:45.292
in their next turn of the conversation,

0:14:45.292,0:14:47.436
how positive or negative[br]they're going to be.

0:14:47.436,0:14:49.134
And these equations, they depend on

0:14:49.134,0:14:51.489
the mood of the person[br]when they're on their own,

0:14:51.489,0:14:54.036
the mood of the person when[br]they're with their partner,

0:14:54.036,0:14:55.915
but most importantly, they depend on

0:14:55.915,0:14:58.614
how much the husband and wife[br]influence one another.

0:14:59.191,0:15:01.816
Now, I think it's important[br]to point out at this stage,

0:15:01.816,0:15:05.209
that these exact equations[br]have also been shown

0:15:05.209,0:15:07.995
to be perfectly able at describing

0:15:07.995,0:15:11.302
what happens between two countries[br]in an arms race.

0:15:11.983,0:15:14.568
(Laughter)

0:15:15.605,0:15:19.408
So that - an arguing couple[br]spiraling into negativity

0:15:19.408,0:15:21.478
and teetering on the brink of divorce -

0:15:21.478,0:15:25.589
is actually mathematically equivalent[br]to the beginning of a nuclear war.

0:15:25.589,0:15:27.818
(Laughter)

0:15:28.456,0:15:30.669
But the really important term[br]in this equation

0:15:30.669,0:15:33.150
is the influence that people[br]have on one another,

0:15:33.150,0:15:36.308
and in particular, something called[br]the negativity threshold.

0:15:36.308,0:15:38.169
Now, the negativity threshold,

0:15:38.169,0:15:42.680
you can think of as[br]how annoying the husband can be

0:15:42.680,0:15:46.758
before the wife starts to get[br]really pissed off, and vice versa.

0:15:47.285,0:15:51.652
Now, I always thought that good marriages[br]were about compromise and understanding

0:15:51.652,0:15:54.587
and allowing the person[br]to have the space to be themselves.

0:15:54.587,0:15:57.892
So I would have thought that perhaps[br]the most successful relationships

0:15:57.892,0:16:00.940
were ones where there was[br]a really high negativity threshold.

0:16:00.940,0:16:02.881
Where couples let things go

0:16:02.881,0:16:05.844
and only brought things up[br]if they really were a big deal.

0:16:05.844,0:16:10.060
But actually, the mathematics[br]and subsequent findings by the team

0:16:10.060,0:16:12.823
have shown the exact opposite is true.

0:16:12.823,0:16:15.377
The best couples,[br]or the most successful couples,

0:16:15.377,0:16:18.554
are the ones with[br]a really low negativity threshold.

0:16:18.554,0:16:22.769
These are the couples that don't let[br]anything go unnoticed

0:16:22.769,0:16:25.710
and allow each other[br]some room to complain.

0:16:25.710,0:16:30.935
These are the couples that are continually[br]trying to repair their own relationship,

0:16:30.935,0:16:33.878
that have a much more positive[br]outlook on their marriage.

0:16:33.878,0:16:35.828
Couples that don't let things go

0:16:35.828,0:16:40.735
and couples that don't let trivial things[br]end up being a really big deal.

0:16:41.402,0:16:46.569
Now of course, it takes bit more[br]than just a low negativity threshold

0:16:46.569,0:16:50.632
and not compromising to have[br]a successful relationship.

0:16:50.874,0:16:53.991
But I think that it's quite interesting

0:16:53.991,0:16:56.367
to know that there is really[br]mathematical evidence

0:16:56.367,0:16:59.642
to say that you should never[br]let the sun go down on your anger.

0:16:59.642,0:17:01.672
So those are my top three tips

0:17:01.672,0:17:04.713
of how maths can help you[br]with love and relationships.

0:17:04.713,0:17:07.025
But I hope[br]that aside from their use as tips,

0:17:07.025,0:17:11.190
they also give you a little bit of insight[br]into the power of mathematics.

0:17:11.190,0:17:15.514
Because for me, equations and symbols[br]aren't just a thing.

0:17:15.785,0:17:20.349
They're a voice that speaks out[br]about the incredible richness of nature

0:17:20.349,0:17:22.497
and the startling simplicity

0:17:22.497,0:17:27.170
in the patterns that twist and turn[br]and warp and evolve all around us,

0:17:27.170,0:17:29.640
from how the world works to how we behave.

0:17:29.640,0:17:31.948
So I hope that perhaps,[br]for just a couple of you,

0:17:31.948,0:17:34.391
a little bit of insight into[br]the mathematics of love

0:17:34.391,0:17:37.672
can persuade you to have a little bit[br]more love for mathematics.

0:17:37.672,0:17:38.795
Thank you.

0:17:38.795,0:17:40.721
(Applause)