Beyond a reasonable doubt
Last night I had a long conversation about what role, if any, probabilistic evidence should have in our reasoning about “the things that matter” (meaning, I suppose, the fundamental structure of our relationships with each other, the world, God, ourselves.) What are we to make of language like this:
- “Considering all the arguments for and against, I hold there to be a 90% chance that God exists, and so call myself a deist.”
- “Considering all the arguments for and against, I’m 95% certain I should marry this woman, and so will do so (if she consents).”
- “Considering all the arguments for and against, I’m 99% sure he committed the crime, and so vote to convict.”
Has it any place in philosophical discourse?
The class for which I’m TAing has recently been reading Plato’s Gorgias, in which Socrates has this to say about refutation (in Donald Zeyl’s translation):
[471e] My wonderful man, you’re trying to refute me in oratorical style, the way people in law courts do when they think they’re refuting some claim. There, too, one side thinks it’s refuting the other when it produces many reputable witnesses on behalf of the arguments it presents, while the person who asserts the opposite produces only one witness, or none at all. This ‘refutation’ is worthless, as far as truth is concerned, [472a] for it might happen sometimes that an individual is brought down by the false testimony of many reputable people. Now too, nearly every Athenian and alien will take your side on the things you’re saying, if it’s witnesses you want to produce against me. […472b…] Nevertheless, though I’m only one person, I don’t agree with you. You don’t compel me; instead you produce many false witnesses against me and try to banish me from my property, the truth.
In other words: truth does not depend on popular consensus. This is not an epistemological claim about how to tell, “objectively,” what is true; it’s an ethical attitude, a decision to live on the estate of truth. Socrates would abandon his rightful property were he to allow the beliefs of others to determine what he holds to be true. But it’s also grammatical: to assent to a statement X, not because one understands it to be true, but because others assent to it, simply doesn’t count as holding it to be true. Knowledge requires understanding, requires being able to stand behind an account (logos) of why what is true, is true. And once Socrates can do so, the number of witnesses on the opposing side doesn’t matter.
But this is not an arrogant Romantic self-reliance; conversation is supremely important to the Socrates of the Gorgias. “[485a] And what kind of man am I? One of those who would be pleased to be refuted if I said anything untrue, and who would be pleased to refute anyone who says anything untrue; one who, however, wouldn’t be any less pleased to be refuted than to refute.” The difference is that conversation means responding to the account the other gives, trying to see whether you too can stand behind it, trying to convince them to join you if you cannot join them. There’s no counting involved. Socrates would not put it in these terms, but would, I think, agree with the following statement: probabilistic attempts at certainty fail because they forget that arguments are made through language, by persons, and seek to enter into the truth; they treat logoi as empirical data points.
So Socrates would have no truck with “Considering all the arguments for and against, I hold there to be a 90% chance that God exists.” That’s fine for practical things (though not ideal), but intolerable (and unethical) when dealing with “the things that matter,” the things that structure how we make sense. But then: can we ever know anything about “the things that matter,” other than that we know nothing? These things, after all, aren’t going to just wait around for us; if we refuse to stand behind any account of justice, or the good, or love, or God, until we understand it fully, we are, in fact, accepting that we will die before we are ready to stand anywhere, to make any sense.
The practical urgency of this dilemma comes out most clearly, perhaps, in the criminal justice system, which (unlike most aspects of our democratic government) requires jury members to be in complete agreement about the guilt of the accused, and requires them to consider that guilt not just probable, but “beyond a reasonable doubt.” That phrase doesn’t, I think, have a formal definition, but I take it to mean “the prosecution must offer an interpretation of the available evidence that demonstrates that it is the only possible interpretation to which any reasonable person could assent.” 99% certainty that he committed the crime is neither sufficient, nor necessary, nor relevant. The jury isn’t being asked to give its best guess, it’s being asked to stand behind the decision it makes.
At the same time, of course, each jury member is told to step outside himself and inhabit the common-sense-driven mind of the “reasonable man.” If I were a philosopher in the midst of an existential crisis, no longer certain that the external world exists, it would be impossible for me to stand behind any judgment I make as to the accused’s guilt or innocence, but if I were to allow that to influence my decision I would fail to properly execute the office of juryman. I would fail, too, if I were a conspiracy theorist who thought that criminals were never guilty, but were always framed by the police. I would also fail in the office of juryman if I refused to vote in accordance with the “reasonable man” of a society that held that people named Jones were always criminals. I don’t think Socrates would much like the legal fiction of the “reasonable man.”
Socrates was known to be courageous in battle, and, of course, when he was on trial in the law-courts. My class is about to read the Apology, where after his conviction and death sentence Socrates has this to say about certainty in the face of death (Grube’s translation)–note, too, what Socrates says about what it means to be a juryman rightly so called:
[40a] To you, as being my friends, I want to show the meaning of what has occurred. A surprising thing has happened to me, jurymen–you I would rightly call jurymen. At all previous times my familiar prophetic power, my spiritual manifestation, frequently opposed me, even in small matters, when I was about to do something wrong, but now that, as you can see for yourselves, I was faced with what one might think, and what is generally thought to be, the worst of evils, my divine sign has not opposed me, [40b] either when I left home at dawn, or when I came into court, or at any time that I was about to say something during my speech. Yet in other talks it has often held me back in the middle of my speaking, but now it has opposed no word or deed of mine. What do I think is the reason for this? I will tell you. What has happened to me may well be a good thing, and those of us who believe death to be an evil are certainly mistaken. [40c] I have convincing proof of this, for it is impossible that my familiar sign did not oppose me if I was not about to do what was right.
His language sounds mystical, but I don’t think he means anything by “prophetic power”/”spiritual manifestation”/”divine sign” other than “the sense I have, because I attempt to live in the truth, of whether or not what I am about to say will exile me from the truth.” He dies a martyr to truth, and that whatever doubts he has about the exact nature of justice, temperance, prudence, courage, piety, etc, he has no doubts about the correctness of this decision.
If anything troubles me about the figure of Socrates in his hagiographic aspect, it is his marriage. His wife was said to be “shrewish,” but that’s likely because Socrates didn’t do anything to support his family, preferring to discuss philosophy all day with whomever would listen. Did Socrates take his decision to marry seriously–the way a philosophically reflective person of today would–or did it happen to him as a matter of course, as something imposed on him by custom, before he began to devote his life to philosophy? The Biblical prophet Hosea married Gomer, a prostitute, as an emblem of God’s love for the unfaithful Israel. If Socrates’ relationship with Xanthippe shows us anything, it shows us the dark side of his view of the body as fundamentally an encumbrance, a nagging annoyance.
The conversation I had last night recalled these passages from Plato to my mind, and today at mass I could not help but be struck by the resemblance between the words of Socrates I quoted from the Apology and the words of the Gospel reading today (Luke 21:10-19, in the Douay-Rheims translation):
 Then he said to them: Nation shall rise against nation, and kingdom against kingdom.  And there shall be great earthquakes in divers places, and pestilences, and famines, and terrors from heaven; and there shall be great signs.  But before all these things, they will lay their hands upon you, and persecute you, delivering you up to the synagogues and into prisons, dragging you before kings and governors, for my name’s sake.  And it shall happen unto you for a testimony.  Lay it up therefore into your hearts, not to meditate before how you shall answer:  For I will give you a mouth and wisdom, which all your adversaries shall not be able to resist and gainsay.  And you shall be betrayed by your parents and brethren, and kinsmen and friends; and some of you they will put to death.  And you shall be hated by all men for my name’s sake.  But a hair of your head shall not perish.  In your patience you shall possess your souls.
Socrates would have no difficulty embracing these words were he told that the logos itself had spoken them. Nor would he take them to be promising a miracle; for him, the immortality of the soul is no miracle, rather the most reliable of truths. But if he were told that it was Jesus of Nazareth, and that what is being promised here is a resurrection of the body? Socrates refuses to say “I hold there to be a 90% chance that it is Good to seek for Truth”; but what about “I hold there to be a 90% chance that the Resurrection took place”? How can knowledge of an historical event, especially an historical event that is by its very nature an exception to the rule, not be empirical, rather than rational? “But we preach Christ crucified, unto the Jews indeed a stumbling-block, and unto the Gentiles foolishness….”