The Argument from Degrees

From the fact that things come in degrees — more and less good, true, noble, real — to a maximum that is the source of them all. Aquinas's Fourth Way: the most Platonic, and the most debated, of the five.

Premises & Hinge

The Argument

The numbered form is ours, after Aquinas's Fourth Way; cf. the SEP, "Aquinas," and Feser's Neoplatonic reading — the words themselves are the philosophers', below.

  1. P1 Things display degrees of goodness, truth, nobility, and being — some more, some less.
  2. P2 Degrees of a perfection are measured against a maximum of that perfection.
  3. P3 The maximum of a kind is the cause of that perfection in everything that has it in lesser degree. the hinge
  4. Therefore there is a maximum of being, goodness, and truth — the cause of every perfection in things — which we call God.

The sources

The Argument Saint Thomas Aquinas 1268
The fourth way is taken from the gradation to be found in things. Among beings there are some more and some less good, true, noble and the like. But _more_ and _less_ are predicated of different things, according as they resemble in their different ways something which is the maximum, as a thing is said to be hotter according as it more nearly resembles that which is hottest; so that there is something which is truest, something best, something noblest and, consequently, something which is uttermost being; for those things that are greatest in truth are greatest in being, as it is written in _Metaph._ ii. Now the maximum in any genus is the cause of all in that genus; as fire, which is the maximum heat, is the cause of all hot things. Therefore there must also be something which is to all beings the cause of their being, goodness, and every other perfection; and this we call God.

Source — Saint Thomas Aquinas, Summa Theologica I, q. 2, a. 3 — the Fourth Way (from gradation)

Continued Saint Thomas Aquinas 1268
God alone is good essentially. For everything is called good according to its perfection … This triple perfection belongs to no creature by its own essence; it belongs to God only, in Whom alone essence is existence … Hence it is manifest that God alone has every kind of perfection by His own essence; therefore He Himself alone is good essentially.

Source — Saint Thomas Aquinas, Summa Theologica I, q. 6, a. 3 — that the maximum of goodness is God's own essence

Argument hinges on:

That the maximum causes the lesser degrees The maximum of a kind is the cause of that perfection in everything that has it in lesser degree. What does that mean?
The library's note

The argument sounds strange to modern ears, partly because Aquinas's own example — that fire, "the maximum heat," is the cause of all hot things — is simply bad physics; heat is not caused by a hottest thing. Read charitably, though, the argument is not about heat but about what medieval thinkers called the transcendentals: being, goodness, and truth — features everything has to some degree just insofar as it exists at all.

A better example helps. The nature of redness is what makes each red thing red; nothing could be red if there were no such nature to share in. Aquinas's claim is that goodness, truth, and being work the same way — a thing is good, or true, or real only by sharing in goodness, truth, and being themselves — and what everything shares in must exist in full, as their source. That fullness, wanting in nothing, he identifies with God.

Everything turns on two steps most people balk at. First, that degrees really do imply a maximum. Some do not: there is no "most distant" thing simply because things are more or less distant. Aquinas needs the perfections in question — being, goodness — to be the kind that have an intrinsic maximum, not the kind that trail off without limit. Second, that this maximum is the cause of the lesser degrees, and is a real being rather than an abstract standard. Critics press on both.

Defenders — most fully today Edward Feser, who reads the Fourth Way through its Neoplatonic roots — answer that being and goodness are not ordinary gradable qualities but transcendentals, and that whatever has them only partially must receive them from something that has them without limit; an abstract standard, having no existence of its own, could cause nothing. Honesty requires a note: the record of sharp, distinct objections aimed specifically at this argument is thinner than for the others, and its liveliest treatment today is within the neo-Thomistic revival. We show it at its true weight rather than pad it.

Written for this library — not a quoted source. It reports how the premise is argued and answered; the philosophers' own words are above.

If you accept it

Accept it, and you take on a broadly Platonic metaphysics of participation — that a thing has goodness or being by sharing in Goodness or Being itself — which much of modern philosophy set aside.
Edward Feser, on the Neoplatonic reading ↗

If you deny it

Deny it, and degrees of goodness and being are left as brute variation with no common source — which some find no easier to accept than the maximum it would replace.
cf. the SEP survey of Aquinas's arguments ↗

Where it leads

Accept that the maximum of a perfection causes it in all else, and this argument leads to a maximum of being, goodness and truth — the cause of every perfection in things.

Beyond the public domain

The modern revivals and their critics are under copyright, so we don't host them — the reading doesn't stop at the public-domain record. Follow it at the sources:

You have read the premise and the cost of each move. The library draws no conclusion. No objection to it is hosted here yet.