Sure, I know what "input" is. But why is it that I'm suddenly hearing the plural everywhere? It's partly, I suppose, that I was taking a course on Global Poverty, and as brilliant as the course was, there was still a fair amount of jargon associated with it. Referring to things as inputs was one of the ways this happened.
My sister then mentioned inputs when referring to her cell phone, and my latest sighting of the word was over at the One Acre Fund, which refers to a farmer carrying "farm inputs" home on her head. One Acre Fund looks like a great project, but as the woman is carrying a brown burlap sack on her head which could contain anything but probably contains seeds, fertilizer and the like, this is not exactly a model of precision in language. Wendell Berry would probably very much disapprove of seeds being termed inputs, though of course I shouldn't speak for him.
My first guess was that inputs comes from computer speak as much as anything, but then I remembered that input and output have been around a bit longer than that, so I'm going to guess that this kind of jargon was adopted more from factory speak. I don't really know why we like to refer to ourselves as machines and farms as factories, but of course we adapt language endlessly, and perhaps that's reason enough.
Although I have to say that when someone says, "I value your input," it very often means they don't.
Okay, so here's a snippet from the Free Online Dictionary regarding usage.
"The noun input has been used as a technical term for about a century in fields such as physics and electrical engineering, but its recent popularity grows out of its use in computer science, where it refers to data or signals entered into a system for processing or transmission. In general discourse input is now widely used to refer to the transmission of information and opinion, as in The report questioned whether a President thus shielded had access to a sufficiently varied input to have a realistic picture of the nation or The nominee herself had no input on housing policy. In this last sentence the meaning of the term is uncertain: it may mean either that the nominee provided no opinions to the policymakers or that she received no information about housing policy. This vagueness in the nontechnical use of input may be one reason that some critics have objected to it.... Though the usage is well established, care should be taken not to use the word merely as a way to imply an unwarranted scientific precision."
The Gift of Good Land, which I highly recommend. The relevant passage is this:
In agriculture, so-called “inputs” are, from a different point
of view, outputs – expenses. In all things, I think, but especially in agriculture struggling
to survive in an industrial economy, any solution that calls for an expenditure to amanufacturer should be held in suspicion – not rejected necessarily, but as a rule mistrusted.
Check out Wendell Berry if you haven't yet. I'm sure my thoughts were formed by him, though sadly not as well as he's elucidated his own. Mainly, I think I can't live up to his vision, but we are kindred spirits all the same...