Without trust, we would have been paralyzed by inaction. I trusted my husband to make a decent cup of coffee, and to drive carefully on his way to the office he says he works in. He trusted me to take care of our kids, and drop them at school as I’d promised.


Trust is essential — we just can’t do everything for ourselves, or check the evidence for everything we believe. We must trust if the are to get what we want, but we must also trust when we’re trying to help others, whether that’s our own children or disaster victims far away.


Trust is at the center of a whole web of concepts: reliability, predictability, expectation, goodwill, and — on the dark side — distrust, insincerity, conspiracy, betrayal, and incompetence.


Economist and social scientists tend to think in terms of rational self-interest: you trust people when you think it’s in their own interests for them to help you, as when the busker expects a share of your immoral earnings. Philosophers tend to be more touchy-feely: you trust people when you think they are good-natured and caring towards you. Evolutionary psychologists tend to think that trust is about reciprocal altruism: you trust people so long as they don’t let you down, since this is a stable, rewarding strategy for all concerned.

For the most part I will understand trust in terms of commitment: when we trust people, we rely upon them to meet their commitments.


The trustworthy person is brave enough to say “no” to commitments she won’t be able to fulfill.


But even if we accept that Blair was sincere, this sincerity is not enough for trustworthiness — it’s not enough to believe what you say, you also need to have good evidence to back it up, especially when the stakes are so high.

The twin requirements of sincerity and knowledge mean that the most trustworthy option is sometimes to say nothing, frustrating though that may be for listeners: with speech as with action, trustworthiness requires judiciousness in making commitments. If you don’t know what you’re talking about, don’t say anything at all.


When we trust someone, we expect them to fulfill their commitment. When we distrust someone, we take them to have commitments but don’t expect them to fulfill these commitments.


Insisting on a distinction between distrust and absence of trust may seem like mere logic-chopping. Yet it’s central to our moral judgments in this area. To distrust someone is to think less of them, to think of them as doing something wrong, however minor. Calling someone “untrustworthy” is a moral criticism, and it’s not something I’d like to hear about myself.


Belief doesn’t seem to be something we can switch on or off at will, whenever it is convenient.


But there may be a middle ground where we can decide to move from uncertainty to trust. If we are genuinely unsure whether someone can be relied upon, we may decide to take our chances and trust her. Such trust can encourage trustworthiness when people react positively to being trusted, and this in turn can justify the original decision to trust.


Some of the benefits and harms generated by trust and distrust are practical — affecting our health, wealth, or enjoyment of life. But some strike more directly at who we are, at our personal integrity and autonomy. Distrust is an insult, not just an inconvenience; corresponding, trust is a compliment. I want my friends, family, and colleagues to trust me, not just because that will make things go more smoothly for me — though it will — but also because I value their high opinion of me, and their level of trust is a key part of their opinion.

Now and again, we could wish for a little less trust. Trust carries expectations, even demands, and if we care about what others think of us, we may wish they would lower those expectations, so that we are not forced to choose between complying and disappointing. Trust can be a burden when we suspect we’re not up to the job, that our best will not be enough.


But I have ignored a crucial complicating factor: communicating our trust can make people become more trustworthy, whilst communicating distrust can generate untrustworthiness. We’re not dealing with a closed, unresponsive system: our judgments about trustworthiness are interventions which can have significant consequences.


Social capital is a feature of social networks — the stronger the network, the greater the capital. It is reflected in levels of “generalized reciprocity,” our willingness to do favors for other people, in the expectation that, somehow or other, in directly, we will eventually reap the rewards.


Living in a society that is rich in such small favors and helpfulness is good for all of us — even for the freeriders who won’t stop to help, but are happy to ask for help when they need it.


If points were offspring, then tit-for-tat strategists would end up with more offspring than others, even in a mixed population where different individuals have different strategies. Those who try to “cheat” — the persistent nonhelpers — will not prosper.


The conditions have to be right for tit-for-tat to succeed. First, there must be some limited resource that is worth more to the recipient than it is to the donor: the blood donation is a small sacrifice from the donor, but it could make the difference between life and death for the recipient. Second, individuals must interact with each other repeatedly; and third, they must be able to recognize each other. Fourth, individuals must be able to adjust their interaction with an individual depending on their past history together.


What are the conditions and circumstances in which people manage to overcome narrow self-interest and cooperate with others? Trust. For Ostrom, the conditions that can promote the development of such trust include a long-term situation, the opportunity to learn about others’ reputations, and the possibility of communication between all the relevant parties.


We’re all good at spotting cheaters, but what counts as cheating depends on where you’re standing.


But there are several other requirements for tit-for-tat: limited resources, repeated interaction, ability to recognize other individuals, ability to adjust our behavior in response to that of others. In the modern world, many of our collective projects involve us with people will never never meet. The apparatus of state, via the police, the legal system, and government, is crucial to creating the right conditions for tit-for-tat, since we as individuals are rarely able to identify and punish those who do not cooperate in these large enterprises.


Calculated risk-taking and trusting are not quite the same, though trusting can often involve risk-taking.


There is no simple step from vomiting bats to the trust and distrust we find in complex interpersonal relationships, where moral categories, and feelings of resentment, pride, and anger, are easily invoked, and we are able to take on explicit commitments to one another.


Oxytocin is sometimes known as the “cuddle chemical,” as it is associated in both humans and other animals with bonding and social contact. But oxytocin also has a more sinister aspect: it boosted cooperation amongst people who already knew each other, but decreased cooperation amongst strangers.


Trustworthiness, thought of as a moral virtue we admire in others, and try to teach to our children, is a matter of living up to our commitment and promises, not just a matter of doing what other people would like us to do. You can be trustworthy without being terribly generous, so long as you follow through when you do offer to help. And you can be kind and generous without being terribly trustworthy, if you have a habit of over-committing yourself, and having to let people down.


Some researchers tried to make the situation more realistic, by rewarding speakers who managed to persuade listeners they were telling the truth. Ironically, this made them look less honest, whether or not they were lying: the more you want to be believed, the more suspicious you look.


Although in fact most people do only slightly better than chance, most of us tend to think we are pretty shrewd. This suggests that we’re much too confident in our own skills. The studies even reveal that the worse people are at telling truth from lies, the more confident they are that they’re getting it right. So a first step towards becoming a better lie-detector is learning to question your own judgment on the matter.


Much depends upon what’s at stake: where studies required people to lie about matters close to their hearts, they gave away more clues to their lying. This makes sense: everyday “white lies” are told without a second thought, and are hardly guilt-inducing for most of us, so are unlikely to take an emotional toll. More significant lies may be harder to manage smoothly, and harder to disguise. But the trouble is that telling the truth about matters close to our hearts can also be stressful, and is likely to induce signs easily mistaken for deception cues. If you’re speaking about something that is important to you, you may appear dishonest even when you’re entirely sincere.


In 17th-century England, some were gentlemen, and some were not. Being gentle required the right combination of wealth, birth, and character, but there was little agreement about which of these 3 was fundamental. Money alone wasn’t enough — the old problem of the nouveau riche — yet poverty made it impossible to maintain basic standards of gentlemanly living and decorum. Being born to a “good” family clearly mattered, though a country squire could be just as much a gentleman as the grand old Duke of York; indeed, the political entanglements of those at the very top of society could make it hard for them to behave like proper gentlemen.

Such proper gentlemanly behavior was the outward sign of inward virtue, though rival traditions valued different sorts of virtue. A chivalric tradition prioritized honor, dignity, and physical courage, but these traits were in tension with the Christian virtues of meekness, humility, and self-control, which underpinned a life pursued with an eye to God’s final judgment rather than to worldly reputation.

Whatever makes him so, a gentleman’s word is his bond. He can be trusted to tell the truth, unlike his unreliable inferiors. He has credibility in the courtroom, as witness or juror, he has credibility in scientific contexts, as reporter of natural occurrences or experimental findings, and he has credibility in everyday life. Laborers, servants, and, for the most part, women, cannot be trusted to speak the truth. To modern ears, this sounds like a nasty bit of class and gender prejudice.


Members are not forbidden from voting or speaking about matters where they have an interest, but the register is supposed to provide the rest of us with some context by which to judge their likely trustworthiness in such circumstances. Motive, motive, motive.

Yet the concept of honor and insult, still with us today, seem to reflect more upon character than on motive. If I openly weigh up what motives my husband my have to lie to me, what troubles he may incur by speaking the truth, then this already indicates a diminution of my trust in him, and he could fairly take offense; all this even if, on balance, I decide it is reasonable to believe what he says.


When we see the mothers or wives of criminals stand by their man, we may pity them, but it’s hard to condemn. Rationality doesn’t require us to ignore our human relationships.


Trusting can also be a way of building trustworthiness — people have little incentive to speak the truth if they know they will be assumed to be lying in any case — and perhaps we have a special obligation to help our loved ones develop their trustworthiness in these ways.


Sadly, being well-meaning isn’t enough. Even concentrating on the possibility of bias, sternly telling yourself not to be prejudiced, can have a counter-productive effect, perhaps because the mental effort involved in concentrating on this point actually makes it harder to resist the stereotypes once you let you guard down. But what is more effective is imagining, or, better still, interacting with people from the stereotyped group who do not fit the stereotype.


Does trustworthiness always require expertise? Not necessarily. We can be trustworthy in areas where we know little, so long as we know our limits. If you don’t know how to cure cancer, that by itself doesn’t make you untrustworthy. But if you don’t know how to cure cancer, yet you confidently start dispensing advice about this, then you make yourself untrustworthy.


Trustworthiness is a matter of meeting commitments, and this requires both good intentions and competence.


Trustworthy people are often good at assessing their own skills, knowledge, and limitations, so that they now when to offer help or advice and when to stand back. Sometimes, the trustworthy option is to say “I don’t know,” or “I’m afraid I can’t do that for you,” even when we know this will disappoint. To be trustworthy to others, we need to be honest with ourselves about what we can realistically manage, and where our weaknesses lie. Over-optimism about our own talents give rise to one form of untrustworthiness.

This kind of self-knowledge is not always easily obtained. Sometimes we can measure our skills and knowledge by external standards, entering competition or passing exams. But often this isn’t feasible, and we may be prone to over- or under-estimating ourselves, depending upon our levels of confidence, or even arrogance. Moreover, this kind of self-knowledge can sometimes require excessive navel-gazing. Achieving accurate, detailed estimation of my own talents and expertise is hardly the noblest goal I can set myself in life.


Rees rejected his friend Stephen Hawking’s view that human would inevitably colonize space — “I think that’s an ill-thought-through statement” — and Hawking’s view that cosmology makes God redundant:

Stephen Hawking is a remarkable person whom I’ve known for 40 years, and for that reason any oracular statement he makes get exaggerated publicity. I know Stephen Hawking well enough to know that he has read very little philosophy and even less theology, so I don’t think we should attach any weights to his views on this topic.


In general, the faster someone speaks, the more competent and knowledgeable they appear to be. In part, this is because fast speakers appear more confident, but fast speech also makes it harder for the audience to spot any weaknesses in the argument or evidence being presented.


In 2003, the Independent newspaper reported the chairman of HSBC boasting that his company had 150 PhD-educated experts evaluating the risk involved in their business.


Finally, we need to be alert to knowledge and expertise that arise from situation and experience, not just from formal education and training.


Sometimes, self-trust seems to involve a divided self, a contrast between the “me” who must decide whether to trust, and the “me” who is the target of the trust — often in the past or the future.


Sometimes I’d pick up practical tips, but mostly I just gained consolation from the fact that others were also struggling with exhaustion, or had emerged from the early stages to enjoy life with their toddler twins. It was salutary to see people managing under much harder circumstances than mine.


10 years earlier, I would have had little or no contact with other parents of twins, let alone triplets. On the other hand, any contact would have been 2-way: I couldn’t have hung out and listened without contributing myself. Super-mum would have found it almost impossible to carry out her fraud face to face — it’s hard to fake 3 babies in real life. Anonymous internet interaction can lead to greater — or quicker — “self-disclosure” than does face-to-face interaction.


Nearly half had lied about their height, and 60% had lied about their weight; men were more likely to exaggerate their height, and women to downplay their weight.


Who amongst us even knows how to write a truthful description of their own personality, and who really knows exactly what they’re looking for in a partner?


Online or offline, there is a danger of a lonely hearts arms race. At the very least, it’s reasonable to expect that others are putting a positive spin on their own situation, appearance, and personality. Once a woman knows that half of all men are exaggerating their height, she’s likely to subtract a little from whatever the next man claims. And if he knows that’s likely, then he may well exaggerate a little more, just to compensate. This is a case where mutual knowledge may decrease both trust and trustworthiness.


But our thinking is not altogether clear: our views about those shady government ministers (trusted by only 17% of us) are driven almost entirely by what those duplicitous journalists (19%) write and broadcast, and, indeed, by what politicians (14%) say about one another. And without journalists, we would have very little idea what scientists say or believe, which would make it puzzling that we give them a 71% rating for honesty.


It is striking that expertise-based professions — doctor, teacher, professor, judge, scientist — are clustered at the high-trust end of the polls, whilst the foot of the table is dominated by professions such as trade union officials, business leader, journalist, and politician, where success is perceived to require skill and energy, but not years of study or accumulation of factual knowledge. We trust the honesty of those professionals whose competence and expertise we cannot directly judge: I must take my doctor’s word for it about what’s wrong with my knee, but I feel free to disagree vehemently with my MP’s view about grammar schools.


The BBC has a charter (as well as an agreement, protocol, policies, codes, and guidance) that sets out its public purposes, its governance structure, and its powers. Purposes include sustaining citizenship, promoting education, stimulating creativity, and “bringing the UK to the world and the world to the UK.” It seems appropriate to think in terms of trust and distrust in judging whether the BBC is doing a decent job in fulfilling those purposes: the better it is doing on these counts, the more trustworthy it is in these respects.


This contrasts with overtly criminal organizations, like the Mafia, which make little pretense of benefiting non-members. While it is right for us to resent the appalling acts and influence of such organizations, it would be peculiar to feel let down or betrayed by them. What else did we expect? In contrast, we have been betrayed by the legal system if indeed it serves primarily to protect the rich and crush the poor.


What is a conspiracy? A conspiracy is a secret plan or action, involving more than one person, to achieve some negative goal. After all, “conspiracy” is a derogatory term, and presumably people involved in such groups who believe in the value of their goals do not think of themselves as conspiring. Within any such group, there is a need for the members to trust each other’s mutual honesty, and trust each other’s competence in the roles they play within the group. But members must also trust each other to be dishonest, or secretive, with respect to the outside world. Again, we see that trust and trustworthiness are not all-or-nothing; people can be trustworthy in one respect without being trustworthy in all respects to all comers, and indeed trustworthiness in one respect (keeping a secret) can positively require untrustworthiness in another respect (lying to the outside world).


Why did the Western European states manage to move relatively quickly from all-out war in the 1940s, to ever-increasing degrees of economic and political cooperation? How do inter-ethnic rivalries grow, and can they be contained?


A different approach is more emotional, or moralized, focusing on trust as relative optimism that another will do the right thing, or act benevolently. This may be the kind of trust envisaged by British politicians and diplomats who speak hopefully about the “special relationship” between the UK and the US: this is supposed to be a relationship built on a long-lasting friendship between the 2 nations, involving cultural affinities and shared values, not just a marriage of convenience between states which happen to find their current interests aligned on the international stage. Indeed, part what is hoped for from the special relationship is that the US will help the UK even when this isn’t obviously in the American national interest.


We must also be cautious in scaling up the attitudes of trust and cooperation at work between individual people to apply to relations between people and states, or between states themselves. States, like corporations, are often treated as quasi-persons, but there are limits to this analogy.


Weak leaders cannot be trusted if they do not have the political capital they need to deliver on their promises, and failed states cannot enter into agreements at all, meaning that they are candidates for neither trust nor distrust.


More generally, the practice of living up to our commitments — being thoughtful about what we take on, but then making sure we follow through — is a form of trustworthiness that has inherent value. The same goes for living up to our commitments in what we say, being thoughtful about what we choose to talk about, being honest, and not representing ourselves as more knowledgeable than we really are. But this kind of trustworthiness can also be of immense practical value, especially where the commitments are worthwhile, to you or to others.