How gratifying to chuck dirty money back in the face of a would-be benefactor. Such moments mark literature. Pip refusing funds from Magwitch, a convict. Will Ladislaw disdaining the charity of George Eliot’s corrupted Bulstrode. The statement is this: scruples do not belong only to the rich. There is a price at which I, too, cannot be bought.

And yet. In these great works of fiction, tensions are drawn out, questions raised. Ladislaw accepts support from another flawed man, Casaubon, of whom he disapproves. Hypocrisy? Or the observation that in a hard world pragmatism has its place – that beggars can be choosers only on occasion? And is Pip right to cast away the reformed and grateful Magwitch? Are all paths to atonement thus to be closed?

Philanthropy is a curious business. What, after all, compels people to give their money away? High-flown principles, yes, but also guilt, vanity, knighthoods, dinner invitations, the need to shore up a battered reputation, the urge to burnish a brand. The hope, also, that having rubbed along in an imperfect world and reached the top, you can at last start to shape it for the better. Out of this mess of human frailty good things come. Fling back too much tainted money and in the end all charities go bust.

To a certain type of purist, though, this isn’t good enough. To them, every coin is dirty, having been forged in the despicable furnace of capitalism. Do they dream of a world in which only true do-gooders give to charity: environmental activists, perhaps, or writers of improving novels? Tricky, because it’s exactly this sort of work that requires philanthropy in the first place. Which brings us to this week’s news: under pressure from activists, both Hay and the Edinburgh international book festival have sacked their main sponsor, the investment fund Baillie Gifford, blowing a mighty hole in their finances. Why? The anti-capitalist group Fossil Free Books has started a campaign against it, claiming it is destroying the planet by investing in fossil fuels, and is furthermore linked to companies that “profit from Israeli apartheid, occupation and genocide”. More than 200 authors have signed an open letter, threatening to disrupt and pull out of events unless Baillie Gifford gets rid of these involvements.

“We were trying to exert pressure on the asset manager to divest, rather than the festival itself,” the activist Grace Blakeley told the Telegraph after Hay’s announcement. But this was never going to happen. As spelled out in Baillie Gifford’s statement, it manages other people’s money. It is not allowed to make ethical decisions on their behalf. As for “links” to the war in the Middle East, the letter speaks of investment in companies such as Nvidia, Amazon and Alphabet. If Baillie Gifford is thereby complicit, so is almost everyone else.

The company seems an odd focal point, in any case, for the fight against climate change. Just 2% of its clients’ money is invested in companies that have business related to fossil fuels – which may include Tesco, for example – against a market average of 11%. A quarter, meanwhile, goes towards cleaner energy. It invested early in Tesla. This is because it specialises in longer term investments, a spokesperson tells me. Fossil fuels are not a good bet and clean energy is.

And with Baillie Gifford gone, will these two festivals be fossil free? Not as long as people drive there, use their smartphones, eat things wrapped in plastic and, yes, buy books. Ink is made from petrochemicals; turning wood into paper accounts for a hefty chunk of industrial emissions. Books are a carbon-intensive product. I don’t mean to knock environmental activism; if the tide is turning, it is thanks to the persistence of these groups. But why Baillie Gifford? A second question: why target it only via its good deeds in the world of books? Plenty of investment managers – and oil companies and arms sellers – do not attempt to pay the piper, and they are left alone. Philanthropists, meanwhile, get heat.

A third. Why book festivals? As the writer Sam Leith pointed out last week, they are not exactly at the nexus of the world’s oil money. What on earth can be the point?

There’s an answer, I think, to all three questions. It is a quirk of human nature to direct our fury not at the worst sinners but at the sinners who will mind the most – and therefore crumble most easily.

Railing against a vast and implacable oil company gets tiring after a while. How much more satisfying to boycott a book festival, an event already bristling with sensitivities – the need to foster balanced debate, appease other sponsors, avoid disruption, head off walkouts from a few panel members? It’s a ripe target. As are authors: it’s surely the worst nightmare of anyone promoting a book to get on the wrong side of a moral culture war. Exert a little pressure here, and a little there, and you might just see results.

It’s no accident, either, that we tend to select our pariahs from among those who try to do good and slip, rather than outright villains. First, they are far more likely to care. Second, a deadly charge can be laid against them: that of hypocrisy. They are pretending to have morals and they do not. Hence punishment falls on associates of associates, rather than the evil itself.

The world has only so much attention to give to climate change. By hammering easy targets, activists are letting far bigger sinners off the hook. And what irony if only the purest among us may now give money in a world famously short on cash. Those who study literature’s moral complexities are learning they have no place in real life.

Martha Gill is an Observer columnist

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