David Hume was born 300 years ago this month. Prompted by the anniversary, many philosophers worldwide will be reflecting on his great works. In the UK this comes at a cost, since doing so deflects us from scrambling to find activities with more immediate and measurable "impact". We can nevertheless find a kind of justification in his writings.
Speaking of the different species of philosophy, in the first part of his Enquiry Concerning Human Understanding (1748), he wrote that "though a philosopher may live remote from business, the genius of philosophy, if carefully cultivated by several, must gradually diffuse itself throughout the whole society, and bestow a similar correctness on every art and calling".
I find it interesting that it is the idea of diffusion that appealed to him here. It did so to George Eliot, too, when in the wonderful final sentence of Middlemarch (1874), she contrasted Dorothea's quiet future with the idealistic visions of doing good with which she had started life: "But the effect of her being on those around her was incalculably diffusive: for the growing good of the world is partly dependent on unhistoric acts, and that things are not so ill with you and me as they might have been, is half owing to the number who lived faithfully a hidden life, and rest in unvisited tombs."
Incalculably diffusive processes are real enough. Education is one of them. Sending a book or an idea into the marketplace may be the datable beginning of a diffusive process, but then there may be no datable end product. William Shakespeare's works diffuse after more than four centuries; Hume's after three. Their works are tributaries into the vast stream of thoughts and ideas and writings and political changes that made the modern world. But nobody can calculate the effect that just one work had, any more than they can calculate just how much of the growth of a flower, or how much of its beauty, was the result of any one raindrop falling on any one day. Yet nobody doubts that rain makes the garden grow. It is an incalculably diffusive process.
I said that nobody doubts these realities, but perhaps I am wrong. For when we think about it, the Higher Education Funding Council for England, for one, does not believe in incalculably diffusive processes. The metaphor of impact, derived from the shuntings of classical mechanics, implies a one-on-one causal sequence. First the billiard ball moves, then it collides with another, and then the other accelerates off: a measurable, datable, visible, verifiable event. We are told that our academic effects must fit into this model, or be counted as nothing. And even if they do, unless the event can be shown to be an improvement, then again it counts as nothing.
This, we may remember, is the hurdle on which Socrates fell, and it is indeed often quite hard to demonstrate improvement. Self-report is no guarantee, for there are processes of corruption that require the victim to feel that he or she is improving as they take place: inductions into cults, for example.
I believe, profoundly, that reading Hume improves almost anybody's mind. But generations of churchmen would have dissented, and thrashing the issue out would be a long business. Although individual researches are often incalculably diffusive, medical science may at least find it easier to tick this box, since we all value health. But whether we value it to the exclusion of everything else may be doubted. I recall the cartoon of two drooling, decrepit men in what is obviously a ghastly old folks' home, with the caption: "Just think, if we hadn't given up partying and drinking, we would have missed all this."
And after all, Jean-Jacques Rousseau first made his name by winning an important prize of the Dijon Academy, arguing that the progress of the arts and sciences had diminished, rather than increased, human well-being. Hume, indeed, quarrelled with Rousseau, but not so far as we know over this.
I suppose when we think about it, having only a reductive and slightly old-fashioned model of causation is making a philosophical mistake, even if the apparatchiks in the Department for Business, Innovation and Skills or Hefce would not know what that meant, nor that Hume made the greatest contribution to the philosophy of causation. But I am not guessing that pointing this out will have any immediate impact, any more than Hume thought that his efforts to enlighten the public would bear fruit before his own death.