Or: The Fine Art of Separating People
from their Bad Behaviours – Online
Copenhagen, June 25, 2009
★★ ★ cbn
2. Life: A Game of Marble Madness
Today, I‘d like to talk about: Immanuel Kant and cloisters, park benches and organ donors, Easyjet and nail polish,
amazon.com, twitter, and why life is a game of Marble Madness. http://en.wikipedia.org/wiki/Marble_Madness
And perhaps, also a little about persuasive web design.
4. (Web) Design ✓
Now, web design we all know (and probably practice).
6. per⋅suadere (lat.):
pierce, get through)
For non-native English speakers (like myself), persuasion comes from the Latin word „persuadere“, meaning „to convince“,
literally: to get through to someone. So, persuasive design is design that convinces people - to do or think differently. Let‘s
take some real life examples.
7. I arrived at this conference by train, starting from here, Hamburg main station, Germany. As in many other European cities, the
station has taken to play classical music in the entrance hall - not to please their travelers, but because research has shown
that it drives off noisy, drunken youngsters who usually don‘t take to Beethoven (a kind of inverse Clockwork Orange). http://
8. Likewise, these arm rests at a public bench in Oxford are not there to give your arms a rest, as one might think, but to keep
homeless people from taking a night‘s rest on the bench.
9. A less mean example are these printed ﬂies in men‘s urinals all over the world, which have been shown to encourage careful
aim and thus signiﬁcantly reduce spillage.
10. Though personally, I much prefer this solution, which adds a design principle I‘ll get to later: Make it a game!
11. small design choices,
In short, persuasive design (as I understand it in the context of this talk) is about small design choices that have a potentially
big impact on the users‘ behaviour.
12. Can we do that
And the question that interests me as a user experience designer is: Can we do that online as well?
13. 3 Rationale
2 Definition 6 Questions
I will answer this question in six steps: We‘re already through with the introduction (1), so let‘s look at what persuasive design
is and what makes it different (2), then why it‘s getting some mindshare right now (3) and whom to ask about persuasion
today (4), before looking at ways to put this into practice (5) and ﬁnally, what questions are still open (6).
15. „I define persuasive technology as any
interactive computing system designed
to change people’s attitudes or
Persuasive Technology: Using Computers to
Change What We Think and Do (2003)
It all started in the late 1990s when Stanford psychologist B.J. Fogg collected everything psychology knew about how
computers change people‘s attitudes and behaviours and did a large study on online credibility, which became a well-
received book and academic research stream under the moniker „persuasive technology“.
16. Make the user follow the
1 designer‘s intent
Design to help the user follow
2 through her own intent
Looking at the applications Fogg described, one might distinguish two kinds of persuasive design: One where the designer
wants the user to adopt a behaviour of the designer‘s choice (like buying something), and one where the designer wants to
help the user turn her own intentions into lasting behaviour changes (e.g. e-health applications like losing weight).
17. 2003 2005 2008
In 2003, designer Andrew Chak ﬁrst applied this notion to websites. Then in 2005, the Eisenberg brothers coined „persuasion
architecture“ as a technique to measure and increase online conversion. But persuasive design really only took off in 2008
with a plethora of white papers, books and blog posts. (Link pointers to all books at the end of the presentation)
18. „You still need good usability—if people
can’t find something they can’t be
persuaded by it—but soon usability will
no longer be the key differentiator it has
Eric Schaffer, HFI
Beyond Usability. Designing for Persuasion,
Emotion and Trust (2008)
For instance, the usability agency Human Factors International re-positioned itself as providers of PET design(tm) or „Design
for Persuasion, Emotion and Trust“. http://bit.ly/17ykn8
19. „Enabling behavior change: ... To
change consumer behaviors we must
design motivational experiences that
push, pull, and ease the pathway to
adopting new habits.“
Brandon Schauer, adaptive path
9 experiences for 2009
Brandon Schauer of adaptive path identiﬁed „enabling behaviour change“ as one of the nine major user experience trends for
20. „Behaviour is our Medium.“
Robert Fabricant, FrogDesign
And in his interactive’09 keynote, Robert Fabricant of FrogDesign went so far as to say that the medium of interaction
designers is not user interfaces nor digital technology - nor any other artifact, but their users‘ behaviour (http://bit.ly/Ypewj,
also check http://bit.ly/uKH5k).
Now you might say: Getting a user to do something online, making it easier for her - isn‘t that usability? In fact, the
characteristics of persuasive design (I think) become much clearer if we compare it to usability.
22. A B
Let‘s oversimplify and say changing a user‘s behaviour is getting her from A (her current state) to B (the desired state).
And let‘s assume that the way from A to B is a slide.
Then usability is all about making that slide as smooth and frictionless as possible, getting all outer obstacles, hurdles out of
the way of the user.
But even the smoothest slide doesn‘t help if the user hasn‘t decided to go for a ride in the ﬁrst place.
26. Persuasive Design!
And that‘s what persuasive design is about: On the one hand, reducing inner resistances and frictions (like fears or conﬂicting
motives) that keep the user from realising her impulse to slide, ...
27. Persuasive Design!
... and on the other hand, amplifying, sustaining or even creating that impulse, that momentum, that motivation to slide.
28. MUST... EDIT...
For we all know that users do use products with horrid usability - if only their motivation is big enough (think Microsoft Word
before its redesign). So a truly rounded picture of a user‘s behaviour has to combine both perspectives: the impulse to do
something and the ease of doing it; the inner and the outer resistances to realising an impulse.
29. Premium Account
2. Exploration New Release
Let‘s draw a ﬁcticious graph of the different phases of a user‘s interaction with a site and the expected and/or felt effort in
doing them. From a usability perspective, the design pain points are obvious: It‘s those peaks of effort that have to be
lowered to ensure the users are not aborting the process.
30. Premium Account
2. Exploration New Release
31. Premium Account
2. Exploration New Release
However, if we layer the felt motivation to do something on top, the real (or at least, different) pain points emerge: Whenever
the motivation to use a site falls below the felt or expected effort to use it, the user will likely leave. Put into a design principle:
32. DESIGN PRINCIPLE
In any step of usage, ask
yourself: Is the felt motivation
to do this bigger than the felt
or expected effort to do it?
33. THEORY OF PLANNED BEHAVIOUR
BI =AB(W1) + SN(W2) + PBC(W3)
This principle basically just applies a well-established model within the psychology of persuasion, the theory of planned
behaviour by Icek Ajzen and others (http://bit.ly/tucLf). Psychologists like to express their models in mathematical formulas, ...
34. THEORY OF PLANNED BEHAVIOUR Persuasion
The intention to perform a behaviour is a result of
the individual attitude and subjective norms
toward the behaviour, and the perceived control
over the behaviour.
... but this one is actually pretty easily translated into human-readable language. Note the emphasis on social factors
(„subjective norms“ means: my subjective notion of what other people expect to be the ‚right‘ behaviour in this situation), and
that „perceived control“ is the result of the outer difﬁculty and my inner ability to overcome it.
35. In summary, if you just increase the usability of a site - not caring about the motivation to use it - and wonder why users don‘t
use it, that‘s like merely turning up the ampliﬁer on a stereo, not the volume, and wondering why you don‘t hear any music.
36. 3 Rationale
But if that is true, why are people only now beginning to pay attention to persuasive design? I see four reasons - three good
and one bad one.
37. The ﬁrst (and bad) one: In the current economic crisis, agencies are looking for any way to differentiate themselves and argue
why they add more to their clients‘ bottom line than their competitors.
38. Reason number two: Within HCI and the behavorial sciences in general, the theoretical models of human reasoning, decision-
making and acting have shifted dramatically. Up until the 1990s, the human mind was thought of basically as an advanced
computer, as expressed e.g. in the GOMs model (http://bit.ly/GtdrQ).
39. A B
1 2 3 4
Traditional HCI understood action and decision-making as a highly rational, functional process focused on completing tasks
and goals. Humans were supposed to start with a clear end goal in mind, systematically slicing up the way into subgoals and
then ticking off subgoal after subgoal until the end goal was reached.
40. However, everyday experience and the new wave of cognitive science tell us that life is really more like a messy game of
snakes and ladders: We are constantly juggling multiple competing, vague goals with likewise competing and vague ways to
get there. Our reasoning, decision-making and actions are inextricably intertwined with our emotions, bodies, artifacts,
environments and social relations. This is what the whole „third wave“ of HCI (like affective computing, social design, user
experience - and persuasive design) tries to articulate and address. http://bit.ly/7klUO.
41. A B
The third reason for the current interest in persuasive design is the expansion of goals that websites are trying to achieve.
Let‘s look at our A-B model again. If I were to tell a webdesigner today that I want to get a user from A to B, she‘d likely say:
„Say no more - I know!“
42. „A - that‘s the Google search result page, and B, that‘s your checkout page.“
Usually, this A-B line is ordered vertically rather than horizontally, ...
... and illustrated with these nifty funnel graphics of how many users you lose on each step on the way.
The technical term for this is „conversion“, and the discipline involved „conversion optimisation“. The current use of the term
conversion is pretty limited to turning trafﬁc on a site into paying customers of whatever service or product the site offers.
46. Goals: Web 1.0, e-commerce
Which is all nice and ﬁne with basic e-commerce sites who‘s conversion goals are basically about selling - exchangig value
However, the word „conversion“ itself already has a much richer history. Originally, it‘s a religious term, signifying a person
changing his or her creed.
48. Goals: Web 2.0, UGC, SNS
Add as friend!
Invite more friends!
Likewise, the range of goals that web 2.0 sites pursue go far beyond traditional e-commerce. They are basically asking their
users to use and recommend their platform more, to create and curate content for free. That‘s neither selling nor employment,
and traditional economics have a hard time modeling the incentives for these kinds of behaviour.
49. (Business Goals)
Advertise for us!
Give us your data!
Create our content!
Curate our content!
Be our customer service!
(Alothough behind the immediate goals, there are - hopefully - still solid, economic business goals.)
50. Prosocial, personal goals
Donate now! Help your neighbour!
Join the cause! Plant a tree!
Write your MP!
Vote for me! Don‘t drink and drive!
And traditional marketing wisdom fully breaks down when it comes to sites that promote pro-social behaviours or try to help a
person change her behaviour. You don‘t „sell“ someone to cease smoking or report potholes on public roads. The dynamics
behind these kinds of behaviour are very different (note though that social marketing claims just the opposite, http://bit.ly/
51. In summary, more and more websites (UGC-based, pro-social, political, e-health, ...) are aiming at other user behaviours than
spending money, and the motives that drive users to do this are not value-for-money. Thus, traditional marketing models
(which are behind most of today‘s online marketing and conversion optimisation) fail to grasp them.
52. Homo Oeconomicus
The fourth and ﬁnal reason is that even with run-of-the-mill commercial transactions, decades of research have shown that
we are not the fully informed, fully rational, always proﬁt-maximising homo oeconomicus that economic theory and marketing
would like us to be.
But if traditional marketing and HCI cannot tell us what drives our users‘ behaviours, the obvious next question is:
54. Whom to ask?
* Erving Goﬀman
* B. F. Skinner
* Michel Foucault
co er gn
no P esi
rom va t
a rket M
Social marketing Health Communica
Sustainable design Propa
i gn rc h
l des Pe
Criti gn ua
The answer is: all of the above, and many more. This (certainly incomplete) graphic shows just the major strands within the
different academic disciplines that might have something to contribute to persuasive design.
co er gn
no P esi
rom va t
a rket M
Social marketing Health Communica
Sustainable design Propa
i gn rc h
l des Pe
Criti gn ua
As a purely subjective selection, there are some that stand out: Apart from the already-mentioned persuasive technology, it‘s
traditional rhetorics and persuasion research, the politics of artifacts in science studies, design with intent (of which later
more), incentive-centered design in CS, and ﬁnally, two ﬁelds within economics that have managed to receive the lion‘s share
of current professional and media attention.
61. Cognitive Neurosciences
The ﬁrst one is cognitive neurosciences and its popular applications. This is often mere psychology repackaged with a more
marketable brand, as the studies most of these books draw upon were published in the 1950s, 1960s and 1970s, without the
imaging technology for brain activity that characterises today‘s cognitive neurosciences.
62. Behavioural Economics
As a look in any current non-ﬁction bestseller list and this Gartner Hype Cycle for 2008 shows, the second up-and-coming
research ﬁeld is behavioural economics. It comprises of economists who recognized that their homo oeconomicus does not
adequately explain (let alone predict) human behaviour.
63. Behavioural Economics
Traditional economic models failed...
... because they looked ... because they ignored
at the wrong incentives systematic distortions
Oversimplifying again, there are two main reactions to this insight: 1. Human beings are economic creatures, we‘ve just
looked at the wrong incentives. If we include the right incentives, the models work ﬁne. 2. Human behaviour really deviates
from rational proﬁt-maximising. However, we can describe these systematic deviations and include them in our models.
64. 5 Strategies
Moving on, how might we as designers include the ﬁndings of all these disciplines into our practice of creating persuasive
experiences? Personally, I have found the 1980s video game „Marble Madness“ to be a helpful visual metaphor to make
sense of human behaviour, and sort the different possible ways to affect it through design.
65. Life: A Game of Marble Madness
In this game, the player navigates a marble through a labyrinth toward a goal. On the way, all kinds of physical forces affect
the marble: gravity, slippery or sandy grounds, rubber bouncers, vacuum devices, ... The ﬁnal course of the marble emergres
from the interplay of inner steering and outer forces - which, I feel, is a pretty accurate concept of human behaviour.
66. * Iconography shamelessly appropriated om Dan Lockton
Seen this way, there are three major strategies in which behaviour (the marble‘s course) may be changed: One might restrict
the pathways that are open, ease the way along certain pathways, or shape the impulses that push or tug in certain
Limit possible behaviours,
exclude unwanted behaviours
Let‘s look at the ﬁrst one: The design excludes deviations from the desired path of behaviour.
My favourite example for these constraints is Immanuel Kant. He had an agreement with his servant Lampe to throw him out
of bed each morning at 7 a.m., no matter what Kant might reason, promise or threaten at that speciﬁc morning.
69. We are all using such self-imposed constraints when we take a retreat in a cloister or health resort. We ﬁnd it too difﬁcult to
get clear or lose weight in our everyday life; therefore, we put ourselves in an environment that automatically excludes all
stimuli and opportunities to deviate from our own goals.
70. Another nice example is this bitter nailpolish for people with a nailbiting tic: Each time they unconsciously start to bite their
nails again, the bitter taste interrupts the habit.
71. The most obvious and blunt form of such constraints in digital media is of course digital rights management that directly
controls what a user can and cannot do with a given ﬁle or application, ...
72. ... or which users are allowed to use it in the ﬁrst place.
73. The checkout process of e-commerce sites is another good example. Once the user has signaled her decision to buy, the
sites immediately remove all information and options that might distract from completing the checkout. The ﬁnal amazon.com
checkout page doesn‘t even offer a back button - all you can do is complete the checkout, or abort it by closing the browser.
74. ClaimID founder Fred Stutzman has created a nifty „retreat app“ to help people constrain their own online procrastination. You
just enter the amount of minutes you‘d like to be free, and the software disables the networking capablity of your Mac for that
75. One might easily imagine a similar functionality on social networking sites that struggle with public accusations of „online
addiction“. Their customers could set themselves time limits for usage.
Gee, time flies! You‘ve already spent one hour
on Facebook today - and you were pretty clear
you only want to join us for that duration each
day. So, please, come and see us tomorrow.
A far subtler form of constraint are defaults. Users generally take the path of least resistance and don‘t change the default
settings, as a study on US driver‘s licenses has shown. The form asked whether the applicant would like to donor her organs
in case of death - and just changing the default from „no“ to „yes“ increased the number of donors by 80%.
78. Default settings are an easy case for persuasive web design. Again, you might further your site‘s goals („receive notiﬁcation
on special offers? Yes!“), or help the user follow hers, e.g. by raising the default security settings (though raising your privacy
settings might also be a way of damaging your competition, see the IE8 privacy settings potentially blocking Google ads).
79. The power of defaults has already been recognized - to the point that being included in the default set is a sellable,
measurable asset. How much would you pay to be included on this page? Put into a design principle again:
80. HOW MIGHT WE...
close off detours from the
without taking away the
user‘s sense of control?
Ease the translation of the user‘s
intentions into behaviours and habits
Let‘s move on to the second family of design strategies: Helping to translate vague, transient intentions („I should ...“) into
concrete, lasting behaviours.
82. Make behaviour visible
There ﬁrst step here ist to make your behaviour and its consequences visible. How many of us would turn off appliances on
stand-by, or unplug transformators, if their cables would signal through bright light that they are indeed using lots of elecrticity
83. „Personal Informatics“
This notion already has its own name: personal informatics. (And if you haven‘t already, check out the mad, beautiful genius of
Daytum-founder Nicholas Felton‘s own annual life in numbers, http://bit.ly/Tazj5).
84. Making the impact of your behaviour visible and measurable is also a common strategy within ecological design. Just add
meters to any kind of daily consumption.
For online procrastination, there‘s RescueTime, which tracks and visualizes which apps and kinds of websites you use for
how long. http://www.rescuetime.com/
86. For your personal energy consumption, there‘s WattzOn http://www.wattzon.com/.
87. Though my favourite example (which will accompany us for a little from this point on) is the social travel network Dopplr,
where you can track your planned trips and check whether your friends will be there at the same time. http://dopplr.com/
88. More interestingly, Dopplr also offers a CO2 calculator for your travels. In September 2008, for instance, I took a transatlantic
ﬂight - and produced around 2 tons of CO2. In December 2008, on the other handy, I did not travel and thus produced no
CO2 - „we envy you“. (Note the subtle emotional difference between this praise and eco-typical admonition.)
89. However, as important as the capturing and making visible of one‘s behaviour is, mere numbers alone produce little
90. Make it personal
The ﬁrst thing to do is to make them personal. There‘s a world of difference between „In 2008, German CO2 emissions
increased by 20%“ and „YOU emitted 4 tons of this stuff“.
91. 4.802 kg
Make it graspable
However, we human beings are terrible with big, abstract numbers. They don‘t make sense. So present those numbers in a
way that is immediately, visually comprehensible, that makes sense and relates to a human scale.
92. 4.802 kg
You will burn 23 trees this year
Make it emotional
Next, try to ﬁnd a representation that also speaks to emotion - in a way that makes sense and adds to the message in the
93. My personal favourite for a numerical display that is personal and emotional is the Deathclock. Enter your date of birth, sex,
weight and height, and it calculates your statistical date of death, with the seconds ticking away live. If that doesn‘t stop your
online procrastination... http://www.deathclock.com/
94. 4.802 kg You will burn The average person
23 trees this year burns 3 trees per year
Make it comparable
Another tactic is social comparison. I produce 4,8 tons of CO2 - is that much? Too much? Is it little? How are others doing?
95. Here‘s a smart example for social comparison used in an utility bill (found on a recent core77 post by Robert Fabricant on
user-centered design for social change, http://bit.ly/bU8M7).
96. 4.802 kg You will burn 23 trees Your aim for 2009: 5 trees
this year, 18 too many (3 less than 2008)
Set (SMART) goals
So let‘s assume you receive a graspable, personal, emotionally appealing depiction of your behaviour: How to translate that
impulse into action? One thing is to offer concrete goals instead of letting the impulse dissipate in a vague „Aw yes, I
should...“. (Think self-management 101 built into the architecture of our designs.)
RescueTime offers exactly that for your computing behaviour: Set yourself goals which kind of software or website you‘d like
to use for how long each day (and receive alerts if you miss your target).
98. 4.802 kg You will burn 23 trees Your aim for 2009: 5 trees
this year, 18 too many (3 less than 2008)
☒ Plant 18 trees instead
☐ Take a train instead and save 4 trees
Offer concrete actions
Then, when there‘s an impulse to act and a concrete goal, offer a concrete action to achieve that goal (easily, without too
much effort) - not some time, but right at the spot where the impulse occurs.
This is the principle of „kairos“ in classical rhetorics, literally the „opportune moment“: To persuade her audience, a speaker
has to address it at the right point in time and space, in the right mood, at the right step within her speech, when the audience
is the most seducible.
Which is why web designers speak of this as the „seducible moment“.
101. A brilliant case in point is this reverse vending machine for deposit bottles. You might either push green (and get a receipt you
cash in at the exit), or push yellow and rather donate that little money - which you actually don‘t have at this point (so it
doesn‘t feel like a loss), is a tiny amount to begin with and saves you the hassle of carrying and remembering the receipt.
102. You will burn 23 trees
This trip burns 10 trees (440 kg CO2): ₤ 12.00
Plant 10 trees
Returning to our Dopplr example: What is the most opportune moment? Not when I enter the trip into Dopplr - by then, I‘ve
likely already booked the ﬂight - but during booking.
103. You will burn 23 trees
This trip burns 10 trees (440 kg CO2): ₤ 12.00
Plant 10 trees
☒ Remember Settings
And then, you might as well add some default to turn this one-time behaviour into a stable one.
104. ☒ Einstellung merken
Which is, in fact, what Easyjet is already doing (albeit only on their English language sites) as a Corporate Social
105. 1. When and where is
the user most
motivated to act?
Translating this notion of kairos into an actionable design principle: When we design a site or application, we should always
ask ourselves two questions. Question one: When and where is the user most motivated to act?
106. 2. When and where is
the user most likely
Question two: When and where is the user most likely to act? Summarised in one sentence:
107. DESIGN PRINCIPLE
No impulse without a fitting
opportunity to act,
no site of action without a
☒ Einstellung merken
Another nice example for multiple facilitating tactics rolled together with kairos is this credit card addon by MIT Media Lab‘s
Sajid Sadi (http://bit.ly/lEVMZ). The user can set personal limits for different kinds of spending, and the card gives a simple
trafﬁc light feedback whether the purchase you just swiped threatens to break the limit.
Design an application that
facilitates individual control of
Of course, it would be even nicer if the card warned you before you swipe it. So as a call to action for this year‘s reboot, I
suggest translating and improving the same problem solution to the web.
110. (If you need more inspiration, IDEO has combined spending with defaults in their Bank of America service design Keep the
Change to encourage saving. All purchases are rounded up to the next even amount, and the difference is added to your
savings account. http://bit.ly/bOMur)
111. Tangential Motivation
The behaviour satisﬁes motives not
directly related to the behaviour
Moving on to the family of strategies concerned with motivation. Here, I see three loose subgroups: tangential, intrinsic, and
extrinsic. The ﬁrst one is to recruit some motive that isn‘t really core to the intended behaviour, but nevertheless satisﬁed by it.
112. Good Gestalt
Here‘s an example: Use gestalt laws. This light switch nudges us to turn off the light (state shown in the right picture),
because we feel the need to reestablish the visual forms that are disrupted when the light is switched on (left picture).
Another good example is our drive towards vissual completion of patterns. Many social networking sites use this as an
incentive to „complete your proﬁle“.
Maybe the smartest way of using this is showcased by Panini football stickers albums; they blend the drive for completion
with other psychological mechanisms of collecting (scarcity, social facilitation) to an addictive mix. (If you‘re too young for
sticker albums, think trading card games.)
115. HOW MIGHT WE...
design interfaces so that the
intended behaviour creates a
good visual gestalt at the
116. Intrinsic Motivation
An activity is in and of itself motivating,
it is its own end
The second group of motivational strategies is to make the behaviour itself so pleasurable, fun and worthwhile that it
becomes and end in itself. And which designers know best how to create pleasurable, fun experiences?
117. „Reality is broken. Games work
better. ... Games are the ultimate
UX Week 2009
Game designers! Or at least that‘s what Jane McGonigal, designer and researcher of Alternate Reality Games, proposes:
Games are „happiness engines“, and game designers should apply their knowledge in creating them to all strands of life.
118. Though beware: Game design does not mean to simply slap points, levels and a highscore ranking on any given activity.
119. A case in point for this simplistic approach is „Attent“ by the Serious Gaming business consultancy Seriosity. They promise to
manage ofﬁce mail clutter by adding a point currency system: You add point rewards to mails according to their urgency, and
receive points attached to mails by replying to them. http://www.seriosity.com
120. A better example is „Chore Wars“, which overlays a complete Online Roleplaying Game mechanic ontop everyday household
chores. Players assume roles and collect experience points by solving „quests“ consisting of household tasks. http://
121. The gaming experience
★ voluntary challenge
★ safe experimentation space without consequence
★ clear goals
★ clear options
★ clear end states
★ clear, strong feedback
★ optimal learning scaffold
★ space and opportunity for socializing
Media psychologists and game designers have sketched ﬁrst theories about why exactly games are such „optimal
experiences“ (see last slides for more references). In general, games are voluntary, save, and much more prestructured and
clear in their goals, choices and consequences than everyday life - but still offer „interesting choices“ on each step.
One very popular model comes from psychologist Mihaly Csikszentmihalyi who extensively studied the shared properties of
„optimal experience“. According to him, we don‘t ﬁnd total relaxation optimal, but challenges where our abilities are fully
called upon: activities that are neither too hard (= stress & anxiety), nor too easy (= boredom). And through many testing
iterations, video games perfectly match their difﬁculty curve with the learning curve of the user. Also, they dynamically adapt
their difﬁculty in any given situation, thus continuously keeping the player in the optimal „ﬂow tunnel“. This is a radical break
with the standard approach of usability to make everything as easy as possible - and I have no easy answer to reconcile this
tension :). http://bit.ly/NrjHf
123. A twist to making the intended behaviour intrinsically motivating is to create an intrinsically worthwhile activity that has the
while reaping the side beneﬁt of a collective bookmark pool), but you can also do it with in terms of pleasure, like the ESP
game: Players have to guess which word their human opponent on the other side will think of ﬁrst when seeing a displayed
picture. In the background, they are really creating high-quality tags for web images. http://bit.ly/y3Imr
124. HOW MIGHT WE...
turn the intended behaviour
into a voluntary challenge
with clear conditions that
creates strong feelings of
125. Extrinsic Motivation
External incentives motivate the
But what if you cannot make your intended behaviour compelling and enjoyable? Let‘s look at the last set of motivational
strategies: extrinsic motivators.
Again, a word of caution: Decades of psychological research have shown that simple external incentives such as money,
grades etc. have only short-term, transient effects and might actually decrease motivation if the user already has other
(intrinsic, social, ...) motivations to do something („I‘m not in it for the money!“).
127. The best one-book summary on this topic is „Punished by Rewards“ by Alﬁe Kohn. http://bit.ly/Buwc6
So, if rewards don‘t work, what kind of motivator does? The answer is (at least on the „social web“): social!
128. Social motivators
★ Peer pressure
★ Social control
★ on and on and on ...
Practically all „social media“ and „social networks“ work so well and develop addictive qualities because they utilize the full
palette of social motivators so masterfully - combined with strategies of facilitation. The list is so long that it warrants another
presentation, so I can only point out two exemplary ones and reference the literature here (i.e. at the end of the slides).
129. Call Visi
Acti to Pref
S ocia l
Just take twitter. One of the most interesting social mechanics (that‘s also used by Facebook status updates) is what I call the
„livestream effect“ of social comparison. The moment I have a couple of „friends“ or „followees“, by virtue of sheer
mathematics, they will collectively produce more updates than I myself - thus constantly encouraging me to post more in
order to „keep up“.
130. Public Commitment
Another social tactic to motivate yourself are public commitments, The PledgeBank by mysociety.org offers a platform where
users can make public pledges and collect social support - „I promise to do X if Y amount of others promise to do the same“.
131. StickK has turned this into a self-help tool: Users can commit themselves to a goal (like losing 20 pounds) in a contract,
deﬁne a (monetary) stake they would lose, and ﬁnd another user as a referee who monitors their progress. https://
So, what‘s missing? There‘s no doubt that persuasive design is just in its infancy. It‘s an unsorted and incomplete toolbox.
133. Open Questions
★ Theory: How does it work?
★ Terminology: How to speak about it?
★ Taxonomy: How to sort it?
★ Methodology: How to apply it?
★ Metrics: How to measure it?
★ Ethics: Isn‘t that immoral?
We still lack models, methods, taxonomies to systematically think and talk about persuasive design, and apply it in our
designs. We lack metrics to test, prove and communicate its effectiveness. And most importantly, we have to answer to
ourselves: Isn‘t this a rather shady business?
134. „Persuasion Architecture“
As regards theory and methodology, in „Call to Action“, the Eisenberg brothers suggested a ﬁve-step method for persuasion
architecture (http://www.calltoactionbook.com) - though personally, I don‘t ﬁnd it very helpful. It‘s basically no different than
any other standard user-centered design process.
135. Quintilian, „Institutio oratoria“
inventio ﬁnding the argument
dispositio ordering the argument
elocutio explicating the argument
memoria rehearsing the argument
actio presenting the argument
Compare this with the classical method for preparing a speech, and you‘ll ﬁnd that nothing much has changed for the past
millennia. (As an aside, listen to Robert "r0ml" Lefkowitz talk on Quintilian as a blueprint for software development, http://
136. Aristoteles, „Rhetorics“
ethos character, credibility of the speaker
pathos speaking to emotion: images, stories
logos speaking to reason: valid arguments
Another valuable classic model are the three main means of persuasion in Aristotle‘s „Rhetorics“: A speech is persuasive by
virtue of the speaker‘s character (online trust, anyone?), appeals to the emotions of the listener, or the validity of the argument
itself. (Idea to look at Aristotle nicked from Colleen Jones‘ beautiful slides on persuasive web copy: http://bit.ly/nW32l).
137. B.J. Fogg, „Functional Triad“
tool increases capability
social actor creates relationship with computer
medium provides experience
social space enables social communication
In „Persuasive Technology“ (http://bit.ly/AQUId), Fogg speaks of three ways computers might persuade us: they increase our
ability to do or persevere, they build a social relationship with us (by providing feedback, praise, etc.), or they convey
compelling experiences. (In his more recent work on Facebook as a persuasive technology, he puts additional emphasis on
the ability of digital technology to connect humans to persuade each other - though the wording „social space“ is my own).
138. Method Cards
Stephen P. Anderson says he‘s currently working on a set of „method cards“ for the different tactics of seducing users.
Though as of today (June 2009), nothing is public yet - apart from this gorgeous presentation: http://bit.ly/zoyG5
As for myself, I keep a huge mindmap that shall eventually become an online pattern library. (Whoever wants to join is
cordially invited: sebastian /ät/ dings /dot/ cc ^_^).
140. Design With Intent Toolkit
Currently, the best and most mature taxonomy and method I know of is Dan Lockton‘s „Design With Intent Toolkit“ - a must-
read, as is his blog „Architectures of Control“: http://bit.ly/18NfOB
141. Mind Control?
I‘d like to close with the question of ethics: Usability ultimately serves the user, persuasive design „manipulates“ users: Isn‘t
that unethical? The usual ethical standards are to avoid deception and outright coercion (the user should always be able to
choose and consent), and to make your own intentions transparent.
142. „You cannot not communicate.“
But then again, just as we cannot not communicate ....
143. „You cannot not ------------
... we cannot not inﬂuence other people. The moment we interact with anyone, we also, by the nature of social interaction,
affect them. So the ethical question is not whether we persuade or not, but (a) how we do it, (b) with which intentions, and (c)
to what effect?
And ﬁnally, we should never forget that there will always be a world of difference between our intentions as a designer ...
... and the uses people invent for our creations.
146. Some Online Resources
★ Dan Lockton‘s blog: http://
★ Fogg‘s Captology laboratory @ Stanford University:
★ Google Group Design and Behaviour: http://
★ The most important conference on the subject, the
annual „Persuasive“: http://persuasive2009.net
147. Books to read
★ B. J. Fogg (2003): Persuasive Technology. Using Computers to Change What
We Think and Do. http://bit.ly/AQUId
★ Richard H. Thaler, Cass R. Sunstein (2008): Nudge. Improving Decisions About
Health, Wealth, and Happiness. http://www.nudges.org
★ Joshua Porter (2008): Designing for the Social Web. http://bokardo.com/p/759
★ Dan Arielly (2008): Predictably Irrational. The Hidden Forces That Shape Our
★ Steven D. Levitt, Stephen J. Dubner (2006): Freakonomics. A Rogue Economist
Explores the Hidden Side of Everything. http://freakonomicsbook.com
★ Mihaly Csikszentmihalyi (1990). Flow: The Psychology of Optimal Experience.
★ Raph Koster (2005): A Theory of Fun for Game Design. http://bit.ly/2rddnB
148. For the sake of completeness (yet not
★ Andrew Chak (2003): Submit Now. Designing Persuasive Web Sites. http://
★ Bryan Eisenberg, Jeffrey Eisenberg (2005): Call To Action. Secret Formulas to
Improve Online Results. http://www.calltoactionbook.com
★ Bryan Eisenberg, Jeffrey Eisenberg (2005): Waiting for Your Cat to Bark?
Persuading Customers When They Ignore Marketing. http://bit.ly/wC8U
★ Susan M Weinschenk (2008): Neuro Web Design. What Makes Them Click?
★ Mark Lindstrom (2008): Buyology. Truth and Lies About Why We Buy. http://