In Jane Austen’s novel Persuasion, the main character Anne is advised by a trusted advisor to turn down a proposal of marriage to Wentworth, the man she loves. As the story unfolds, Anne comes to see that the advice she took was poor advice. When Wentworth reappears on the scene years later, she is urged yet again to follow money and status rather than her heart. This time she is older and wiser and has the wherewithal to make up her own mind. She makes her own judgment and rejects the advice of the once trusted advisor.

The choices Anne makes encapsulate for me two important aspects of persuasion: trust and evidence. In her youth, Anne trusted her advisor, Lady Russell, who had taken an interest in Anne and had served in some ways as the mother that Anne had lost. Anne had no reasons not to trust Lady Russell and every reason to trust her. The difficulty arose when Anne’s feelings ran counter to Lady Russell’s advice. How now should she decide?

As Anne matured, she had the chance to observe many people and many marriages. Her observations lead her to see those who pursued wealth and social status as shallow and foolish. Marriages based on mutual respect and love, on the other hand, were joyous and stable. Thus when she was again faced with a choice between the suitor with status and the suitor with whom she shared love and respect, she chose the latter. It was not a difficult decision.

Now let me be clear that I am not trying to suggest that trusting is foolishness or poor judgment. Nor is trust opposed to evidence; our trust is built upon the evidence of another’s repeated trustworthiness and character. On the contrary, I think that trusting others is one of the most reasonable and necessary things that we do as human beings. To not trust precludes the possibility of deep relationships. To trust and be trusted is central to loving and being loved. In fact, God commands us to trust Him for our needs.

Yes, trust is a good thing. But all good things can be perverted: the greater the good, the more devastating the perversion. Marriage, for instance, is based upon the trust spouses have for each other. When that trust is broken, the pain and damage is correspondingly deep. Among trusted friends, we are occasionally confronted with passionate convictions. If the friend is mistaken, then placing our trust in him can lead us to becoming deceived, however unintentional that deception might have been. On a larger societal level, trust can be abused in the form of propaganda. Seemingly trustworthy experts use “truths” in a way that steers us inexorably to their desired conclusion. Trust on its own is subject to error and deception.

How, then, stands evidence? Is it not also subject to error and deception? Certainly it is, and we must, as in the case with trust, use skill and judgment when evaluating evidence. Nevertheless, evidence is an extremely valuable tool in our search for truth. Well-meaning people have differences of opinion, and it is by weighing the evidence that we can come to a decision. Evidence is particularly important in public debate when strong interests and motives are at work.

However, it is the relationship between trust and evidence that I find most interesting. In particular, it seems to me that each is dependent on the other. As much as we would like to think otherwise, a very rational argument using sound evidence will rarely persuade a listener who does not trust the arguer. While the argument appears to the listener to have no flaws, yet he thinks some subtlety may have been overlooked. Perhaps a mistake exists in the reasoning or the assumptions. To examine the argument and all its assumptions and evidence takes a great deal of work; it takes skill and desire and is not always worth the trouble. Thus if we do not trust the arguer, we are predisposed to disbelieve. In my youthful evangelical zeal, for example, I engaged in a number of conversations with fellow physics graduate students about Christianity. These students were masters of the use of evidence and argument. Surely if anyone could be persuaded by the evidence for Christianity, it would be them. I mustered not one argument, but four cogent arguments for the existence of God. Needless to say, I had no conversions to report. Prior to these conversations, I had not gained their trust as someone worth listening to. They had already decided the issue, and my attempts were wasting their time, not prompting them to further reflection.

On the other hand, when we trust the arguer, we are predisposed to believe. In this case, we are less likely to pick apart the arguer’s words. The evidence can stand on its own and be evaluated. But here the opposite error is common. Rather than denying the evidence without weighing it, we accept the evidence without weighing it. No pastor was ever censured while “preaching to the choir.”

Thus it seems that evidence depends on trust. But it is also the case that trust depends on evidence, as I mentioned above. We trust a particular person or group because we have evidence that the person or group is worthy of our trust. Our experience provides that evidence, and without it, we are less likely to grant that trust.

One of the best examples of the intertwined nature of trust and evidence is our belief in Jesus. If we do not trust God, no amount of evidence is sufficient to bring us to trust Him and the evidence He has provided concerning Jesus. If we do trust God, then we are in a place where we can examine the evidence pointing to Jesus and deepen our trust both in God and Jesus. Yet, God does not want us to trust Him without evidence. His trustworthiness is a central feature of the Bible. He has provided ample evidence to the Hebrews and to the gentiles that He is and that He is trustworthy.

Despite the necessary link between trust and evidence, I am concerned that the link is eroding. Our culture is one where evidence is becoming less and less, well, trusted. My purpose here is not to discuss this trend in detail but rather to note some of its features. For example, society now sees arguments strictly as techniques used by those trying to obtain a desired end. The ends may be diverse—for example, convincing the public to accept particular governmental policies or to reject ideas that do not conform to the current scientific paradigm or to buy certain products and not others—but the means are the same. For those who use arguments as techniques, arguments which achieve the end are good arguments and those which do not achieve the end are bad arguments. Society at large thus sees evidence and argument as aspects of manipulation, and no one wants to be manipulated. Couple this view with a growing belief in the near impossibility of determining the truth in any particular situation, and evidence no longer has any great value.

So, as evidence is devalued, we are left with trust. But while I maintain that trust is good and necessary, trust without evidence can be dangerous. More and more, however, our culture is accepting trust itself as evidence. If a trusted source has vouched for a plausible belief, we are inclined, out of respect or friendship, to accept that belief. If the trusted source’s belief is aligned with my preconceived ideas, so much the better. We trust our friends and mentors, as we should, but friends and mentors are not infallible, and no true friend or mentor would want us to forsake our own pursuit of truth.

Persuasion, then, requires both trust and evidence. Without trust, evidence often falls upon ears that will not hear. Without evidence, trust is blind and leaves us at the mercy of our culture. Jane Austen’s character Anne shows great growth and maturity. She gained valuable evidence that allowed her to judge what was important. She did not stop trusting, but she learned to do so wisely. Our lot in life is to persuade others and to be persuaded; that is part of our search for what is true. Thus the question is not whether we will persuade (or be persuaded), but whether we will do so wisely or poorly.