Skip to the content \ accessibility

« »

Accessibility versus affordance – Unasking The right Questions

Unasking The right Questions – By Bill Thompson.

Accessibility has always been an issue for information and communications technologies, but for most of the 60 or so years we’ve had stored-program digital computers, it was a secondary consideration.

Getting physical access to early computers like EDSAC and ATLAS involved being in the right room in the right city at the right time, whether or not you were a wheelchair user or had poor vision.

When the number of people with easy and affordable access to the new technologies of desktop computers, network access and online publishing tools was relatively small, accessibility for those who needed special provision could be handled using one-off solutions, often built by those concerned since they were technical themselves.

Over the years this has led us to design systems for the majority and then adapt them to work for those who are somehow different, and we keep thinking about ‘accessibility’ and ‘usability’ as separate, almost orthogonal aspects of design. Unfortunately, this remains the dominant model, and it has now become a barrier to future progress because it encourages designers to think about creating tools and services for the ‘normal’ population before considering accessibility.

We need to change this approach, and to move away from solving the ‘problem’ of accessibility to a view of design in which it stops meriting separate consideration.

We need to stop giving designers the opportunity to talk about ‘accessibility’, and instead collapse the distinction that is causing us so much trouble.

Instead of thinking about ‘access’ at one end and ‘usability’ at another, we should attempt to recast our debate in terms of what technology does for all of us, not just those whose have ‘special’ requirements.

After all, technology is there to mediate between us and the world, and all technology is about changing, enhancing or correcting our bare capabilities to allow new things to be possible, transforming the otherwise inaccessible and unperceivable into sense data, or subjecting the physical world to the influence of enhanced motor skills.

How many of you can see the moons of Jupiter with your naked eye, or run at

The additive power of technology is as true of the telescope and the car as it is of the internet. Technologies sit between us and the world and allow us to perceive it more intimately, measure it more precisely, influence it with greater precision and scope, and reach out to others without concern for distance or – in many cases – language.

They do that for us all, irrespective of our capabilities. But different technologies offer different affordances, depending on where we encounter them and – most importantly – our own capabilities. We can only use a telescope to see the craters of the moon if we have adequate vision, though of course interpreting the data from a radio telescope does not necessarily require this.

We have too often been content to build technologies which only serve to enhance the capabilities of the ‘modally-abled’, those whose physical and cognitive abilities cluster around the modal value for modern humans. We clearly disregard those whose abilities are much lower than the norm, but also tend to forget those who may be better – they tend to cope, of course, and do not usually ask for special attention.

So how should we frame our debate if we move beyond what I think is a dangerous attempt to retain the distinction between ‘usability’ and ‘accessibility’? I think it is time to explore the idea of ‘affordance’, as it could offer us a way forward.

Bill Gaver, Professor of Design at Goldsmiths College, has an interesting take on this. In a 1996 paper, he wrote: “Affordances go beyond value-free physical descriptions of the environment by expressing environmental attributes relative to humans. For example, the physical measure of height, which has no inherent meaning, can be recast in terms of the affordance of accessibility, which does. Because accessibility emerges from the relation between elevation and people’s physical characteristics, it is an objective fact about a situation.”

The idea of accessibility – here used to mean whether a shelf or window can be reached – as something which emerges from a relationship between a technology and a user is one we might build on in our attempt to reconcile the usability-driven design approach and our concern over whether people can use specific technologies.

The key is the interaction between the technology and what it offers and the ability of the user actually to make use of that offer, as it allows us to sketch out a model of augmented capability that covers all of us, not just those who might be classified as ‘disabled’ in some way.

If we start to frame the issues facing users whose capabilities deviate from the norm in terms of affordances rather than simply of accessibility, this might free us from the ‘modal totalitarianism’ that infects so much design, whether in products like screens and keyboards or on-screen in websites, widgets and services.

Affordances matter equally to the ‘abled’ as to the ‘disabled’, and so the same design methods can be used, and outcomes can be evaluated in a much broader way. This allows us to start to move away from the current model, in which we have ‘assistive’ technologies to overcome ‘deficits’ that make some users ‘abnormal’, to one in which we all have skills and abilities that vary along a large number of axes.

This is going to be very important in the near future, as those of us who first encountered digital technologies when we were young and able-bodied, begin to age. I wear glasses to read from the screen, and I know that my high-frequency hearing has been damaged by years of gigs and loud music in headphones.

I can feel my cognitive abilities going, and can see a world where I will be, as Shakespeare might have put it, sans eyes, sans teeth, sans keyboard, and in the near future I will need assistive technologies even more.

If we think differently about design and consider issues of accessibility in terms of affordances, then we may move closer to another goal – that of exposing and understanding the impacts of the negative ‘externalities’ of unusable sites and services.

To an economist, externalities are effects on parties that are not directly involved in a transaction, such as the impact of a polluting factory on the health of non-employees in the surrounding area. The costs of the transaction do not therefore reflect its full costs or benefits, once these externalities are taken into account. Externalities can be positive, such as the network effect that comes from more and more people using an online service, or negative.

By and large, businesses will try to bring more of the positive externalities in-house – we might see battles over copyright as an attempt by rights-holders to internalise all the benefits of creative reuse – but keep negative externalities away, and off their balance sheet.

A more integrated approach to design, however, one that classes all users as equal and equally deserving of service, could make it harder for those who disregard the needs of the non-modal population to treat the costs as an externality to be met by extra funding, charitable engagement or personal expenditure on assistive technology. And by bringing the costs back to those who have given us this world of dysfunctional technology, we might persuade even the accountants and management consultants who have for so long disregarded the needs of anyone outside the mainstream, that there are sound financial reasons for becoming more inclusive.

We would not even need to tax them to achieve this (though this would be one approach): we could nudge them to do the right thing by offering benefits and tax breaks for those whose choices are more in line with this point of view, perhaps limiting access to government support services, guaranteed bank loans and the other benefits that businesses are currently calling for, to those who will offer tools, sites and services that can be used by all taxpayers and not just those with 20/20 vision and high levels of manual dexterity.

The transition from the current approach, which we could call modal oligarchy, to one of design for all, will not be easy. Those of us within one standard deviation of the mean may worry that elegant tools and desirable products that ‘just work’ will no longer be available, that innovation will be limited and that we will have to work harder to get what we want from websites.

But no user interface is intuitive, no keyboard obvious, no website ‘natural’. Just as learning language rewires the human brain, so learning how to use network computers requires us to link old skills in new ways. We’ve taken the easy path so far, but I would speculate that interfaces designed for all will not only be more usable by mainstream adopters, they will be more powerful.

And they will unleash a wave of creativity not only from those of us who are already well served but from the millions upon millions who are currently excluded.

If we believe in the transforming power of these new technologies, if we want the network revolution to succeed, and if we desire the best and brightest to join us in this brave new world, then we need to ensure that the barriers to access are removed at all levels. That means campaigning to bring down all of the digital divides, not just the one between rich and poor but between the majority of users for whom most technology is designed and those of us whose capabilities lie more than one standard deviation from the mode.

The conversations taking place at this conference, e-Access ‘09, are part of that process, but I think it is time to push for something more. I think that this should be the last e-access conference. Next year I hope to see you all here for e-affordance 2010.


Post a comment

Comment spam protected by SpamBam