There is a tantalizing puzzle here. The nature of mind is at the heart of Buddhism. Buddhism uses introspection to investigate this nature, rather than fMRI machines or photomultiplier sensors. Curiously, the general structure of the Buddhist investigation is to attempt to grasp the mind through ever subtler means and to discover the futility of every such attempt. But perhaps that futility was simply a matter of inadequate technology. Now, finally, are we becoming able to reveal in stark contrast what has remained in the shadows for millennia?
It is a bit of an odd question to contemplate. Certainly methods such as fMRI reveal many intriguing regularities in neural behavior, and correlations between these and various cognitive behaviors. What sort of phenomenal pattern might justify our exclamation, "Ah, there it is, the mind!?"
Our experience of our own mind is intimate in unsurpassable degree. Looking at others, it's quite a mystery. People seem to be an unravellable tangle of sparkling insight and blind automatism. Indeed, reflecting on one's own behavior, it is often embarrassingly easy to find instances that trigger one to ask, "What was I thinking?"
At the end of the 19th Century, physicists were homing in on their goal of discovering the nature of the ether, the medium that carries electromagnetic waves such as light. Einstein's breakthrough realization, the Theory of Special Relativity, revealed that the ether was an illusion, that light is not the sort of thing that is carried by any sort of medium. One could say that light is its own medium: the changing electric and magnetic fields of one moment generate the fields of the next moment. The ether was to provide a frame of reference in which the behavior of electric and magnetic fields had a logical structure. In its place, the Theory of Special Relativity outlines the relationships among an infinite family of frames of reference, in every one of which electric and magnetic fields have the same logical structure.
I would like to propose that the scientific discovery of the nature of mind might well turn out to be surprisingly compatible with the teachings of Buddhism. The mind is what perceives and what acts, much as the ether carried electric and magnetic fields. Just as the ether provided a fixed frame of reference from which to understand electromagnetism, the mind is the locus of our confrontation with the world. Just as the realization of the non-existence of any privileged frame of reference paved the way for understanding how to work with multiple frames of reference, so might the realization of the nature of mind open us to vaster perspectives. The locus of confrontation between mind and world is not anything fixed but a frame of reference from which appears a history of experience.
Does our perceptual and active confrontation with the world actually seem to have any such sort of shiftable character?
Quantum measurement provides a first exhibit. Between some quantum phenomenon such as a photon and the ultimate act of observation, there is a whole chain of intermediary physical systems, such as a photomultiplier tube, an impulse counter, an eye, a brain; we are free in our analysis of the system to stop anywhere along this chain, treating as the quantum system as much of the world as we choose, and the remainder as the classical observer. The shiftable character of mind is very clear in this case.
Consider the puzzle of global warming as another very different exhibit. Allow me to stipulate that indeed the continued combustion of fossil fuel at the present scale will lead to ecological catastrophe and thence human catastrophe. What is to be done? The frustrating and intriguing nature of this question is that it depends on just who is the doer under discussion. As the human race, our options are straightforward enough: we must dramatically reduce our net emission of greenhouse gasses. Of course, how such coherent action might emerge out of the tangled mass of planetary humanity… that is a daunting puzzle! But the puzzle is not much less daunting however one shifts the boundary between observer/agent and world. What should the United States of America do as a nation? What should the United State Federal Government do? What should the State Department do? What should the American Association for the Advancement of Science do? What should I as an individual do? Perhaps I need most to steer somehow the thinking of the American public on this issue, and that might require me to increase my consumption of fossil fuels, flying about to various meetings etc.
A similar sort of shiftiness is apparent in the puzzle of diet, as outlined by Gary Taubes in his book Good Calories, Bad Calories. Clearly the simple energetic relationship must hold within rather strict bounds, between dietary consumption of calories, expenditure of calories in physical activity, and storage of excess calories in fat. The difficulties arise in examining consumption and activity. A famished person will stop at little to find and consume food, and if frustrated will succumb to lethargy. To what extent is any individual's behavior a function of clear perception and free choice, and to what extent are we driven by the physiological imperatives of blood sugar, insulin, etc.
There is not merely philosophical value to a clearer understanding of the division of experience into an observer/agent and a world, of how that division is itself not a feature of the world but logically prior to the world, of how our choices of how to make that division give rise to our options for exploring and guiding the unfolding of our experience. For example, in macroeconomics there are many institutions that participate in the economy as they try to understand and guide it. Are their regular patterns of institutional intervention part of the system which those interventions are intended to steer?