This Saturday I acquire my first kid-in-law, when one of my two sons marries. I’m supposed to be happy for the couple, and I am indeed happy. Not only that, I’m happy to participate in a ceremony wherein many of their associates create common knowledge about our willingness to spend resources to collectively declare our happiness about this marriage. But I wonder: what does this fact say?
We often celebrate general symbols, as with holidays. When we celebrate particular people we know, we often celebrate accomplishments, as in elections, graduations, sport wins, and retirements. Sometimes we celebrate nothing in particular, as with birthdays, just to have an excuse to get together.
But I see our more heart-felt collective celebrations as choices to commit: marriages, baby showers, baptisms, citizenship, and commitments to join groups as doctors, soldiers, and nuns do. It makes sense to celebrate commitments together, if a community is supposed to be part of the commitment. Committing to each other seems one of the most heart-felt things we ever do.
It seems to me that our most hopeful and heart-felt commitment celebrations are marriages and baby showers, which are of course related. And this suggests that these are among the most important commitments we make, not just as individuals, but as communities offering our support to individuals.
Our society today doesn’t support monogamy and marriage as strongly as did ancestral societies. We have far weaker legal and social sanctions against those who divorce, don’t marry, or cheat on marriages. When some express strong criticisms of marriage, others usually don’t take much offense or argue against them very vigorously. We even allow and often encourage experiments with other arrangements.
But the unparalleled joy and hope we feel at weddings, and perhaps baby showers, and our eagerness to participate in them, are real data, not to be ignored. These feelings say that we see these events as very important, and we guess that getting married or having kids is on average a better choice than staying single or childless. We accept that people must make their own choices for their lives, but on average we hope for marriage and kids. Especially we parents.
Commitments are choices to neglect future preferences. Staying with a spouse or a child for only as long as you feel in the mood in the moment is not a commitment, and our deep hope and celebration of these commitments says that we see such neglect as often wise. You may not always be happy with such choices, but a commitment to them can bring deep satisfying meaning to your life.
We don’t often say these things directly or our loud. But you can see us saying these things by the way standing with you at your wedding, beaming with hope and pride.
I'd suggest part of the difficulty here is that there are multiple senses in which we can say X is the reason people do Y.
Speaking informally we often say X is the reason that people do Y when introspectively X is what comes to mind when people think about it, i.e., they aren't lying. I think in this sense the reasons mentioned above are a substantial reason that people have marriage ceremonies.
However, I suspect that you are more interested in a kind of causal/counterfactual reading, e.g., if X wasn't true than we wouldn't do Y. I think it's in this sense many of the signalling based explanations are true even if people are not consciousnessley aware of them.
I largely agree with your analysis but I don't think the happiness and joy expressed at weddings is evidence that we think it's a better choice generally. It's merely evidence that we think it's a better choice for those who are inclined to make it (the same way we can celebrate the choice to become doctors, priests and other professions without believing that people who choose a non-doctor profession are worse off).
I happen to think we do believe marriage is a better choice I just don't believe this particular behavior is evidence for that claim.