The scientific and manifest images

by Neil Rickert

In 1960, Wilfrid Sellars gave some lecturers on the Scientific Image of Man and the Manifest Image of man.  These were later published, and seem to be available on the net as a pdf file.  Roughly, the scientific image is how the world looks to science (particularly physics), while the manifest image is how it looks to us.

Right now, I am looking at a table (actually, my desk).  And it presents itself to me as a solid object with a smooth surface.  That solid object can be said to be part of the manifest image.  However, science describes it as mostly empty space, but with an array of atoms.  The atoms are separated by space.  To science (that is, to physics), there really isn’t a surface nor anything particularly smooth.  This array of separated atoms in space is part of the scientific image.

Why the difference?

I will mainly be looking at the differences between those images, and discussing why there is such a difference.

In recent posts, I have been discussing how we get information about the world by means of carving it up into parts.  The way that we carve up the world gives us the manifest image.  The way that science carves up the world gives us the scientific image.

As discussed in earlier posts, science carves up the world into abstract entities (space, time, mass, force, etc).  It can see the table as an array of atoms separated by space, because of the way that it carves the world up in terms of space.  This requires great precision in dividing up the world.  To get that precision in spatially carving up the world, it needs to anchor its observations quite precisely.  Or, as I have put it previously, it needs to follow strict external standards.

We, as human observers, cannot carry out such a fine spatial dividing.  Our head, and thus our eyes, are moving all of the time.  We cannot depend on precise external standards, for if we bound to such standards then we would not be autonomous perceivers of the world.  So we are unable to see the amount of detail in dividing up space.  Instead, we see the surface of the table as uniform and smooth.

Science (or physics) is not very good at dividing the world up into objects.  We pick up a can of soup at the grocery store, and take it to the checkout counter.  The computer that scans our items cannot recognize that can of soup.  But it can recognize the pattern of the bar code.  Scanning the bar code, it gets a number that it can look up in a database which tells it that the bar code is for a can of soup.  The way that the scanner sees the world is closer to the scientific image, and that image cannot really tell what is an object.

In a recent news report, we heard that a self-driving Uber automobile struck and killed a pedestrian.  The NTSB (National Transportation Safety Board) examined the evidence available, and concluded that the automobile sensors did indeed detect the presence of the pedestrian.  But apparently (my interpretation), they failed to recognize that what they were detecting was an object (or a person).  That’s an example of where the scientific image differs from the manifest image.

From the point of view of science, it is examining and carving up space.  The pedestrian shows up as some sort of spatial change.  But the pedestrian is moving, so that spatial change is itself varying all the while.  As human perceivers, on the other hand, we will tend to lock onto to that pedestrian.  We do not have external standard to fix our positional observations.  So the edge of the pedestrian serves as a temporary local fixed point that we can use as we carve up the world.  So we tend to carve around such objects, and that makes the objects very apparent to us.

Looking at this in terms of pragmatics, our vision evolved to allow us to notice objects, for that ability to see objects is important to our way of life.  Physics had different goals in its examination of space and time, such as the ability to predict future motion of projectiles that we launch.

Thus we see, at least in part, why the way that the world appears to physics is different from the way that the world appears to us.

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