U.S. Transportation Secretary, Ray LaHood, announced earlier this week that federal government will crack down on drivers’ cell phone use. The announcement comes a week after the Virginia Tech Transportation Institute issued a press release of a study that shows that texting and talking while driving dramatically increases the risk of collision. This is just one among many studies pointing to similar conclusions (including the infamous study that the National Highway Traffic Safety Administration didn’t publicize for allegedly political reasons). The results are hardly surprising. As Secretary LaHood commented, “We all know texting and driving is dangerous.” So, then, if it is so dangerous and we know it, why do we do it?
Philosophers of action might be inclined to say that this is a textbook case of akrasia. Indeed, when you answer your cell phone behind the wheel you seem to behave like the dieter who, giving into temptation, accepts a second helping; or, the unhappy spouse who has a one-night fling. Some predominant desire of yours (e.g. to answer the phone right then) takes over, motivating you to act contrary to your better judgment.
Yet, is this right? When you answer the phone are you really acting against your better judgment? Don’t you, instead, act under the impression that, if you make the effort, you can do well both things, talking and driving? And isn’t this, rather, a textbook case of miscalculating one’s abilities.
However, if this is true about this case, then it also seems true about most alleged instances of akrasia. You know what you are doing is wrong. Yet you do it, because you over-estimate your capacity to compensate for it, or you under-estimate the impact that your decision will have. You say to yourself: “I can burn all these calories tomorrow,” “My spouse will never find out,” etc.
Related articles:
Desire
By Tim Schroeder, Ohio State University
(Vol. 1, October 2006)
Philosophy Compass
The Natural Philosophy of Agency
By Shaun Gallagher, University of Central Florida
(Vol. 2, Februrary 2007)
Philosophy Compass
The Philosopher's Eye 
How are akrasia and self-deception related? Does the latter rule out the former? Or is self-deception (in cases like those described) somehow part of akrasia?
Self-deception does not rule akrasia. You might act against your all things considered judgement and confabulate about the true motives behind your action. You can also act akratically, in part, as a result of being self-deceived about your ability to resist temptation.
An interesting question your comment raises is, perhaps, this. Does akrasia occur when one is self-deceived about one’s all things considered judgment and one acts contrary to what one thinks is all things considered better. Is this a case of akrasia, or a case of enkrasia?
Incidentally, miscalculating one’s abilities need not result from self-deception