This book is about commitment. But what are the hard, philosophical questions that commitment, in general, raises? Isn't there a disturbing vagueness in the title, as if commitment were just one thing, when perhaps it is really multifaceted? Many things come to mind when we think about the concept. There is, most obviously, the idea of responsibility. A manufacturer's warranty explains “our commitment to you” in respect of the product or the quality of service. A bank says it is committed to “the highest standards of customer service” (whether or not that is the case). A doctor is committed to acting in the patient's best interests; he or she gives them priority over all else, and must never allow them to be subordinated to other concerns, such as financial ones. Commitment, more generally, has connotations of steadfastness, dedication, a refusal to be deflected from the task at hand. The person who is committed, say, to his profession can be expected to be reliable in it. Someone in a “committed relationship” can be expected not to leave it, or not without very good reason.

For these sorts of reasons, the idea of commitment is often associated with promises or undertakings. A sincere promise implies a genuine commitment; if someone promises you something, you have a right to expect that person to deliver on it. We thank people for promising to do certain things for us. But we do not thank them for promising, as such, but for acting on that promise in future. In other words, we thank them in advance.