Scholastic regress arguments

Many arefamiliar with arguments to the effect that an infinite regress of causes isimpossible, as Aquinas holds in several of his Five Ways of proving God’sexistence.  Fewer correctly understandhow the reasoning of such arguments is actually supposed to work in Scholasticwriters like Aquinas.  Fewer still areaware that the basic structure of this sort of reasoning has parallels in otherScholastic regress arguments concerning the nature of mind, of knowledge, andof action.  Comparing these sorts ofarguments can be illuminating.

Causality

In Aquinas’sFirst Way, he famously argues that it is impossible for there to be an infiniteseries of movers or changers, so that a regress of changers must terminate in afirst unchanging changer.  As I’vediscussed in many places (such as at pp. 69-73 of my book Aquinas), Aquinas is not claiminghere that no causal series of anykind can regress infinitely.  Rather, hehas in mind a specific sort of causal series, which commentators sometimes call“essentially ordered series” and sometimes “hierarchical series.”

Heillustrates the idea with a stone which is moved by a stick which is in turnmoved by a hand.  The stick moves thestone, but not by its own power.  Byitself the stick would simply lay on the ground inertly.  It can move the stone only because the handimparts to it the power to move it.  Thehand too, of course, would be unable to move the stick (so that the stick inturn would be unable to move the stone) unless the person whose hand it is deliberatelyuses the hand to move it. 

Thetechnical way of putting the point is that the stick is a secondary cause in that it has causal efficacy only insofar as itderives or borrows it from something else. By contrast, the person who uses the stick is a primary cause insofar as his causal efficacy is built-in ratherthan being derivative or borrowed.  Thestick is a moved mover insofar as it moves other things only because it isitself being moved in the process.  Theperson is an unmoved mover insofar as he can move the stick (and, through it,the stone) without something else having to move him in the process.

Aquinasgives other arguments against an infinite regress in such cases, but this isthe one I want to focus on here.  Thebasic idea is that there cannot be secondary causes without a primary cause,because you cannot have borrowed or derivative causal power without somethingto borrow it from.  This would be true nomatter how long the regress is, and it is important to note that infinity assuch is not really what is doing the work here. Even if we allowed for the sake of argument that the stone in our examplewas pushed by an infinitely long stick, there would still need to be somethingoutside the stick to impart causal power to it. For a stick is just not the sort of thing that could, all by itself,move anything else, no matter how long it is. 

Nor, forthat matter, would it help if the causal series in this case went around in acircle rather than regressing to infinity – the stone moved by the stick whichwas moved by another stick which was moved by the stone, say.  For sticks and stones just aren’t the sortsof things that could move anything by themselves, even around in a circle.  There would have to be something outside thiscircle of movers that introduced motion into it.

Meaning

Now considera second and at first glance very different sort of argument, which isassociated with John of St. Thomas (John Poinsot) and was defended in thetwentieth century by Francis Parker and Henry Veatch in their book Logicas a Human Instrument.  Itappeals to a distinction between instrumentalsigns and formal signs.  An instrumental sign is a sign that is alsosomething other than a sign.  Consider,for example, a string of words written in pen on a piece of paper.  It is a sign of the concept or propositionbeing expressed, but it is also something else, namely a collection of inksplotches.  Now, there is nothing intrinsic to it qua collection of inksplotches that makes it a sign.  Byitself, a string of splotches that looks like “The cat is on the mat” is nomore meaningful than a string of marks such as “FhjQns jkek$9(quyea&b.” 

Suppose wesay that the string of splotches that looks like “The cat is on the mat” hasthe meaning it has because of its relations to other strings of splotches, suchas the ones we see in a dictionary when we look up the words “cat,” “mat,” etc.  That can hardly give us a completeexplanation of how the first set of ink splotches get their meaning, becausethese new sets of splotches are, considered just by themselves, as meaningless as the first set.  They too have no intrinsic meaning, but haveto derive it from something else.

Notice thatwe have a kind of regress here.  And whatthe argument says is that this regress must terminate in signs that do not gettheir meaning from their relations to other signs, but have itintrinsically.  This is what formal signsare.  And unlike instrumental signs, theymust be signs that are not alsosomething else – that is to say, they must be signs that are nothing but signs.  With a sign that is also something other thana sign (a set of ink splotches, or sounds, or pictures, or whatever), themeaning and this additional feature can come apart, which opens the door to thequestion of how the meaning and the additional feature get together.  But a sign that is nothing more than a sign just is its meaning.  Because it just is its meaning, it needn’tderive or borrow its meaning from something else.

The argumentgoes on to say that these formal signs are to be identified with our conceptsand thoughts, which are the source of the meanings that words and sentenceshave.  This in turn provides the basisfor an argument for the mind’s immateriality, as I discuss in Immortal Souls.  The point I want to emphasize for the moment,though, is that we have here an argument that holds that a regress of itemshaving a certain feature in only a derivative way can exist only if there issomething having that feature in a built-in or non-derivative way – which is,at a very general level, analogous to the reasoning Aquinas deploys in theFirst Way.

(As a sidenote, I’ll point out that John Haldane, in Atheism andTheism, develops a line of reasoning which might be seen as anamalgam of these two arguments.  Aperson’s potential for concept formation, he says, presupposes fellow membersof a linguistic community who actualize this potential by virtue of already possessingconcepts themselves.  But their potentialto form these concepts requires the preexistence of yet other members of thelinguistic community.  This regress canend only in a first member of the series, whose possession of concepts need notdepend on actualization by previous members. This “Prime Thinker” he identifies with God.)

Knowledge

A third lineof argument, once again very different at first glance but ultimately similarin structure, concerns epistemic justification. Consider the “problem of the criterion,” of which Michel de Montaignegave a famous statement.  In orderrationally to justify some knowledge claim, we will need to appeal to somecriterion.  But that criterion will inturn have to be justified by reference to some further criterion, and thatfurther criterion by reference to yet some other criterion, and so on ad infinitum.  It seems, then, that no judgment can ever bejustified.

As theNeo-Scholastic philosopher Peter Coffey points out in his Epistemology or The Theory of Knowledge,the fallacy in this sort of argument lies in assuming that the justificationfor a judgment must in every case lie in something extrinsic to the judgment itself.  The skeptical argument fails if there arejudgments whose criterion of justification is intrinsic to them. 

Now, supposeit can be established that we cannot fail to have at least some genuine knowledge.  Onemight argue, for example, that even the skeptic himself cannot coherently raiseskeptical doubts without making certain presuppositions (such as thereliability of the rules of inference he deploys in arguing forskepticism).  Then we would have a basisfor an argument like the following: We do at least have some knowledge; wecould have no knowledge unless there were at least some judgments whosecriterion of justification is intrinsic to them; therefore, there must be atleast some judgments whose criterion of justification is intrinsic to them.

The point isnot to expound or defend this sort of argument here.  The point is rather that such an argument wouldbe a further instance of the general pattern we’ve seen in the otherarguments.  In particular, it would beanother case in which it is argued that there can be a regress of things havingsome feature in only a derivative way (in this case, epistemic justification)only if there is something having it in an intrinsic way.

Action

One lastexample, which concerns action. Aristotle, and Scholastic writers like Aquinas following him, hold that everyaction is carried out for a certain good, and that good is often pursued onlyfor the sake of some further good to which it is a means, which is itselfpursued for the sake of yet some other good. The regress this generates can terminate only in some end that ispursued for its own sake, as good in itself. Naturally, there is a lot more than that to the analysis of action andthe good, but the point is to emphasize that once more we see an instance of anargument fitting the same general pattern we’ve seen in other cases.  A regress of items having a certain featureonly derivatively (in this case, goodness or desirability as an end) canterminate only in something that has that feature intrinsically.

Here aresome features common to such arguments. First, and to repeat, the basic general pattern is to argue that theexistence of items having a certain feature in a borrowed or derivative waypresupposes something having that feature in an intrinsic way.  In one case the feature in question is causalpower, in another it is meaning, in another it is epistemic justification, andin yet another it is goodness or desirability. But despite this significant difference in subject matter, the basicstructure of the inference is the same.

Second,although the arguments are set up by way of a description of a regress of somekind, the length of the regress is not actually what is doing the key work inthe arguments.  In particular, thearguments, on close inspection, are not primarily concerned to rule outinfinities.  Rather, they are concernedto make the point that what is derivative ultimately presupposes what isintrinsic or non-derivative.  This wouldremain the case even if some sort of infinite sequence was allowed for the sakeof argument.  For example, even aninfinite series of causes having only derivative causal power would presupposesomething outside the series which had intrinsic causal power; even an infinitesequence of instrumental signs would presuppose something outside the sequencethat was a formal rather than merely instrumental sign; and so on.

Third, thearguments all essentially purport to identify something that must be true ofmetaphysical necessity.  They are notmerely probabilistic in character, or arguments to the best explanation.  The claim is that there could not even in principle be secondary causes withoutprimary causes, instrumental signs without formal signs, and so forth.  The arguments intend to identity thenecessary preconditions of there being such a thing as causality, meaning,knowledge, or action. 

Hence, whetherone accepts such an argument or not, the claims of empirical science are notgoing to settle the matter, because the arguments are conducted at a leveldeeper than empirical science.  The verypractice of empirical science presupposes causality, meaning, knowledge, andaction.  The arguments in question, sincethey are about the necessary preconditions of those things, are also about thenecessary preconditions of science.  Theyare paradigmatically philosophical in nature.