There may be circumstances in which you wish to ascertain whether your dog is barking up the wrong tree. I wouldn’t know; I don’t keep a dog myself. But I can imagine a situation where such knowledge could prove critical. If I speak of the matter in the abstract, that is because of a total lack of hands-on dog-based experience on my part. Some might argue I am precluded from pronouncements about the issue – if we can call it an issue – by dint of this lack, but I beg to differ, much as a dog might beg for a bone from his master’s table. Note that in spite of a deep ignorance of dogs and their ways I am yet able to pluck from the storehouse a vivid illustrative example of common dog (or doglike) behaviour to get my point across. Let those who scoff be hushed, so we can get on with it.
Though for present purposes we need consider only an abstract dog barking abstractedly up an abstract tree, I find that concrete examples can be a boon to the dimwit. Not that I think for one minute that anyone reading this is a dimwit, you understand. Still, it is best to be on the safe side, and a scribbler never knows if or when his words may fall into the clutches of a dunderpate. So for our examples let us take one dog and four trees, a mastiff, say, and a pine and a larch and a sycamore and a wych elm. However unlikely it may be in the real world, let us say there is, in the middle of nowhere, that is in a vast and otherwise featureless flat expanse of land, a row of four trees, planted in a straight line, equidistant, with roughly six yards between them. Blot everything else out of your mind. Well, everything except the dog, which you need to remember, though it has not yet entered the scene. So far we just have the line of trees, the pine and the larch and the sycamore and the wych elm. We could have a line of more, or slightly fewer, trees, but four is a manageable number for the dimwits.
Now, look! Here comes a monkey, scampering towards the trees at high speed. I did not mention the monkey earlier, partly because I did not wish to overtax your brain and partly because, in any case, it will soon be out of sight. The monkey, you see, is being pursued by the dog, the mastiff, and is hurtling pell mell towards the line of trees, up the trunk of one of which it will climb with breathtaking monkeyish agility, and then conceal itself in the high leafage. This duly accomplished, the monkey is, as promised, out of sight.
Enter the dog, panting, in hot pursuit. Those of you who are keen on dogs may wish, at this point, to form a closer bond with our abstract mastiff, so let us dub it Desmond. Imagine Desmond now, stopping short of the line of trees. It is intelligent enough to realise that the monkey must be hidden high up in either the pine or the larch or the sycamore or the wych elm, but not sufficiently savvy to know, just yet, which one. I ought to point out here that I hold no opinion either way on the intelligence of dogs, nor do I have a clue whereabouts in the hierarchy of canine intelligence the mastiff can be placed, as compared, say, to a boxer or a dachshund. Let us credit Desmond with enough nous to realise that, as the monkey is no longer visible anywhere in the vast featureless flat expanse of land, it must have climbed and hidden in the leafage of one of the trees. Remember that Desmond is only an abstract dog, after all.
We now come to the nub of the matter. Desmond thinks that by barking at the foot of the trunk of the tree atop which the monkey is hiding, he can somehow persuade the monkey to climb down and deliver itself into his, Desmond’s, waiting paws. At least, I assume that is what is going through the head of any dog that barks up any tree at its quarry. Whether this is sensible behaviour is another matter entirely. Quite frankly, if I was the monkey, I’d stay put. But we must deal with the world as it is, not as it ought to be, and in the world as it is the dog would bark up the tree, especially if it has been driven to distraction by the antics of the fleeing monkey. That seems plausible.
But which tree does Desmond bark up? According to basic probability theory, the likelihood is that he is going to bark up the wrong one. You can work through the permutations in your head if you like. One of the reasons I limited the line of trees to four is so that you could do so without becoming number-dazed. Add just one tree to the row, for example a cedar, and the chances of Desmond barking up the wrong one grow ever greater.
If Desmond barks up each tree in turn, for a period of, say, a minute or so at the foot of each one, he will sooner or later, to your untold relief and mine, bark up the right one. That is, unless we throw in an added complication. The monkey, being a monkey, might well be agile enough to leap from treetop to treetop, thus from larch to pine to sycamore to wych elm and back again, so that at no point is Desmond barking up the right tree. In these circumstances, we could aver, without fear of contradiction, that Desmond is barking up the wrong tree. Conversely, though the monkey of his original pursuit may avoid the dog’s barking, there may be loitering, in each of the trees, other creatures, such as squirrels, of close or even equal interest to a panting barking desperate mastiff. So you see, even in the simplest concrete example drawn from abstract propositions, things become hopelessly, hopelessly entangled. ‘Twas ever thus, in the wide wide world.