Tuesday, October 21, 2014


For a while, I've thought that:

  1. Hair is not alive.
  2. Every part of me is alive.
  3. So, hair is not a part of me.
This goes against the wisdom embodied in court precedent which has, I understand, held that cutting someone's hair without consent is battery rather than, say, theft.

Interestingly, in L'usage de la Raison, Mersenne talks of the human as a microcosm and mentions that humans, like the universe, have non-living parts, and gives hair as an example. So Mersenne denies (2). And on further reflection, I don't think I really had much reason to accept (2). Indeed, there seem to be other clear counterexamples to (2), such as the electrons in my heart (they are parts of my heart, and parthood seems transitive, at least in this case). Maybe one could argue that while the electrons are at least a part of a living part of me, hair isn't a part of a living part of me. But that would beg the question. For if my hair is a part of me, it's also a part of my head, and my head is surely a living part of me.

So I don't see much ground for denying that hair is a part of me. It's just one of my many nonliving parts.

Of course, speaking fundamentally, there is no such thing as hair (just as there are no hearts, chairs, stones, etc.). There is only I, who am hirsute.


Michael Rabenberg said...

The last paragraph makes me think that you might want to affirm (2) after all. Yes, every part of AP is alive, for AP has exactly one part--the improper part that is identical with AP--and AP is alive.

Heath White said...

What is the motivation for thinking that (nearly) ANY proper part of me is alive? For example, in what sense is my arm alive? Only in the analogical sense that it is part of a living human body. It will certainly not be alive if it ceases to be such a part, but I will not have *killed* my arm.

Alexander R Pruss said...


Maybe better vocabulary is "is a living part". We make a distinction between dead skin and living skin, dead cells and living cells.

Dagmara Lizlovs said...

I've got the following question:

Is the hairdo on Gottfried Wilhelm von Leibnitz for real or is it a wig?

Other people (real and otherwise) with some seriously famous long manes:

Troy Polamalu

If you want to add facial hair, I guess it's a tie between ZZ Top and Duck Dynasty.

I think Troy Polamalu has Leibnitz beat in the hair department. What do you think?

Alexander R Pruss said...

That was the time of amazing men's wigs. I don't think a wig is a part if the body. Nor an artificial leg. But I don't know where to draw the line. I think that transplanted parts do become a part of you, maybe even if transplanted from another species.

Heath White said...

FWIW, I could believe that a blood cell was a living part of my body. But I am not inclined to view my blood as a living part of my body. (Or alive.) This should not be too surprising, since a collection of living things is not in general itself a living thing. But maybe it makes it less obvious what one is getting at with "living part" or "alive".

Alexander R Pruss said...

I think it's not unreasonable to think of the blood as an organ of oxygenation.

(I don't have L'Usage with me right now, but I think Mersenne may have listed blood as another example of a non-living component of the human being.)

Michael Gonzalez said...

Pruss, I think you jump to hastily from cells-in-arms being alive to arms-themselves being alive. I think Heath was correct to say that there is no real sense in which arms or legs are "alive". Cells that compose them are alive for the same reason we are: They meet the biological definition(s). These are somewhat vague, but a cell clearly meets the criteria, while an arm almost surely does not.

So, the only living parts of you are (plausibly, and pace Mersenne) the cells that make you up. Even if they weren't parts of you, so long as they kept doing what living things do (taking in resources and excreting; multiplying according to their kind; etc) they would be living.

So, I think there is a fundamental problem in your initial analysis, dealing with the idea of having "living" parts. Indeed, I think the flora in your gut are more properly considered "living" than is your head... and yet there may be an interesting question of whether we should consider gut flora "parts of ourselves".

Dagmara Lizlovs said...


"That was the time of amazing men's wigs. I don't think a wig is a part if the body. Nor an artificial leg. But I don't know where to draw the line. I think that transplanted parts do become a part of you, maybe even if transplanted from another species."

Kind of like Joe Dirt who had a mullet wig installed when he was a baby because the top of his skull had not formed. I have a hard time deciding who has the better wig - Leibnitz or Joe Dirt. I'll go with Joe Dirt on this one. :-)