A practical case on why we need the humanities

Completely and strongly disagree with both of these.

Even in the sciences, there are many who value gaining knowledge for knowledge's sake, for the joy of discovery, and for a better understanding of the world -- quite apart from its utilitarian value in "reliably recreating some effects".

Now on to the humanities... just a couple of examples:

Do you feel that you know your children, your siblings, your lover, or your parents? Is the point of that knowledge to recreate some effect? Or is that not "real knowledge"?

Historians write about what happened, and would probably consider themselves to be imparting knowledge, but they are not necessarily after giving people the power to recreate some effect.

Now on to your claim that literature and philosophy are about how to live good lives. This sounds like a view influenced by the ancient Greeks and Romans, and is about a couple of thousand years out of date. Both literature and philosophy have grown in many different directions since then (though even then this was hardly the only aim of literature or philosophy), and plenty of people who work in both fields don't concern themselves with the aim of how to live a good life.

Plenty of literature in the last century, for instance, is about pointing out the futility of trying to live a good life, or the absurdity of life, about humans constantly and inevitably being frustrated in their striving to live any kind of life, about going mad, about going in circles, about failure. The Existentialists were some of the most well known of such authors, but there are thousands of others.

Representatives of analytic philosophy have often sneered at the aims of ancient philosophy, such as trying to find what it means to live a good life, and have (in an echo of scholastic philosophy) instead often focused on endless technical minutia such as analyzing sentence structure or logical forms of argument.

Some other forms of philosophy are more about pointing out underlying assumptions. Yet others point out problems with these assumptions, such as Hume's critique of causality. And others still, such as some phenomenologists or the cognitively-oriented analytics, are more interested in describing how perception works or what phenomena appear. Yet others are interested in what we can know, what reality is, or what science is, etc.

Sure, some philosophers are still interested in how to live a good life, or what makes for a good life.. but that is a rather specialized and narrow concern of a relatively small number of philosophers, and there's a lot more to philosophy in general than that.

Incidentally, Francis Bacon had a highly scientistic view, and believed that every field should be more like the hard sciences, and that science was the only legitimate or best way of understanding the world (a view you seem to be echoing). Many people in the humanities do not agree with this view.

at the same time, it's not like they just thought you could make up whatever bizarre misreading you wanted about the text -- you had to present some kind of convincing internal evidence for your reading. even the standards of new criticism rule out a lot of interpretations.

as an outsider it seems like there's a lot of debates in humanities fields that are like that -- what perspective gives the best view of things? what is worth talking about? what kind of evidence and argument is acceptable and convincing?

but it's almost always the case that there are standards, even if people within disagree on them and even if there's no hope of getting to one objective truth.

(there's a lot of very dubious and poorly-done literary criticism, but the same is true of every STEM field.)

If the purpose of teaching the humanities is to teach kids sound reasoning, good writing, and effective persuasion, then why is so little of that evident today when more kids than ever go to college?

Even when goals are the same you can have disagreement over how to achieve them. When goals and values are in conflict, i.e. people have different agendas, we need a mechanism for deciding how to end these conflicts. That mechanism is politics, expressed as some combination of persuasion and violence, how we form, sustain and define communities.