Actual agents go towards one thing as opposed to another, and so their action is toward an end.

We should never overestimate our powers to know what this end is- in most cases we do not know it, and we probably never will know it. We can only know that there is some end, not what the end is in particular.

In the case of the sorts of motions considered most “scientific”; i.e. inertial motions, chemical changes, energy conversions, etc, we have no idea what exactly the end is, and we perhaps never will. The reason for this is that inanimate things perform no action for their own sake, since such action is proper to living things. It is therefore unnecessary, and perhaps impossible, to say (for example) that some radioactive substance gives off isotopes for the sake of the radioactive substance, or that an inanimate object floating by in space is attaining some good for the floating object itself. Inanimate things have no selves, and therefore cannot act for themselves. See Questio disputata de anima a. 13 co. in inanimate things what happens is from some extrinsic agent, in living things, it is from some interior agent. The sense here is not that inanimate things are totally inert: St. Thomas knew about fire, lightening, magnets and falling stones. The sense is that the action of the inanimate does not constitute a self motion, which no one disagrees with. For an account of life as self motion, see Summa theologiae I q. 18 a. 3 co.


  1. Peter said,

    February 27, 2009 at 9:09 am

    I sense that there is some kind of distinction to be made here. Perhaps between proximate and remote ends (or partial and perfect)? I only have a second, but my thinking is something like this. We know things have ends how? From induction. We regularly see stuff tending toward this and not that. This is perfectly clear in ourselves, clear enough in animals, somewhat vague in plants, and only identifiable under experimental situations at the chemical level. If we cannot see in ANY way something as its end (a regularly identifiable tendency?), how then are we making the induction that there ARE ends?

    In other words, how does your statement make sense — “We can only know that there is some end, not what the end is in particular” — if we know there are ends from induction, and induction goes from the particular?

    Perhaps we are thinking of different things….?

  2. Peter said,

    February 27, 2009 at 9:25 am

    On the other hand, we can’t have induction without final causality… perhaps my thinking above is dumb.

  3. Peter said,

    February 27, 2009 at 12:30 pm

    Hmmmm. My objection above doesn’t seem right to me now….
    If the end is that for the sake of which something is done, do we need to know that something to know that a thing is ordered to it?
    On the other hand, doing X doesn’t mean X is the end. It just proves that there is ordered-ness that requires the doing of X. So perhaps we don’t know what that something is. But doesn’t that just make X an intermediate end? I get some water to quench my thirst, but I walk to get some water; but I move my legs to walk, and so on….

  4. Mike Flynn said,

    February 27, 2009 at 1:45 pm

    OTOH, even if they are not self-acting, inanimate motions do tend toward an end. Usually this is the position that minimizes a potential function:a lowest point, a Lagrangian point, a stable orbit. The chemical reaction goes to a conclusion “always or for the most part.” Oxygen and hydrogen, when combined, produce water and not a cucumber salad.

    Perhaps there is a distinction between “end” and “purpose”?

  5. February 27, 2009 at 11:42 pm


    I should have taken that point more into consideration. There is a sense in which they have ends simply as motions caused by some agent. My point here is that the motion is nto for the sake of the things moving, as it is in living things. When you see an object floating by in space, you can know that there was some end involved in its motion, but you can also conclude that it is not an end that benefits the floating object. We must invoke mind at the root of things, What’s more, a mind moving by love of things. Love acts, mind knows.

  6. Agellius said,

    March 3, 2009 at 8:50 pm

    James writes, ” Inanimate things have no selves, and therefore can act for themselves.”

    I think you meant to say “cannot act for themselves”?

  7. March 3, 2009 at 11:29 pm

    oops. fixed it.

%d bloggers like this: