The marriage of Joseph and Mary

Super Flumina

under the patronage of St Joseph and St Dominic

By the rivers of Babylon there we sat and wept, remembering Zion;
on the poplars that grew there we hung up our harps. . . Ps 136

St Dominic


Philosophy behind this website

Professor Solomon's Introduction to Philosophy

For young readers:

Myall Lakes Adventure

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    There are four species of motion, generation, increase, alteration and local motion (motion in respect of place), as Aristotle shows.[1]  Generation involves production of a new entity; this is motion in respect of form for a new form drives out the old in the material substrate.  But local motion is prior to motion in respect of form since that involves the act of that which is more imperfect as Aristotle proves.[2]  And the imperfect is for the sake of the perfect.  St Thomas Aquinas builds on these truths in his Summa Contra Gentiles Book II:

“[I]n the natural order posterior things are caused by things prior.  Therefore motion with respect to form is caused by local motion.  The first local motion, however, is that of the heaven.  Hence all motion towards form is brought about through the mediation of the heavenly motion.”  [Ch. 43 n. 6]


Given its physical separation from the earth’s surface, the modern reader will be bemused by his reasoning.  The heaven, or the heavenly body (Aristotle’s aether), St Thomas asserts to be the first simple body through which all others are sustained.[3]  Aristotle’s reasoning, which St Thomas adopts, is that the motion of the heavenly body is circular, the most perfect form of (local) motion, because it is not corrupted when it reaches the terminus (since beginning and the end are the same).[4]  This body must then be the most perfect among material bodies, more perfect than any body comprised of the natural elements which, in the limited experimental science of their times, the philosophers held were but four: earth, air, fire and water.


In my study How the Universe Operates I suggested that the findings of modern experimental science demanded that the philosophers’ teaching on the heavenly body be amended to remove the assertion that it enjoyed a motion proper to it, circular motion, and to assert in lieu that circular motion is the proper effect the heavenly body induces in its inferiors.[5]  Moved by comments such as that of St Thomas that the heavenly body, aether, is that through which all other bodies are sustained, I contended that it is not to be regarded as confined to the heavenly regions but is universal and, indeed, is the matrix in which all common material beings exist somewhat as the sea is the matrix of all the fish and other creatures that inhabit it.


Incidental to this latter contention there arose the issue of the involvement of aether in the production, including generation, of new entities through the combination with matter of substantial (or accidental) form.  St Thomas wrote:

“Aristotle… reckons the heaven [aether] among the elements, although an element is something out of which things are composed… However, while the heaven does not enter into the composition of mixed bodies it is involved in the composition of the whole universe as being part of it…”[6]

I argued from this that aether cooperates with first metaphysical accident quantity in binding the atomic and molecular structure of each bodily substance.[7]  The teaching of St Thomas in Book II of the Summa Contra Gentiles cited above, “all motion towards form is brought about through the mediation of the heavenly motion”, amended so as to reduce circular motion from an attribute of the heavenly body to no more than its proper effect on all bodies of common material being, seems to confirm that view.


Michael Baker

August 8th, 2023—St John Vianney, Curé of Ars

[1]  Aristotle, Physics IV.

[2]  “It might seem that genesis could claim the priority among movements on the ground that the thing must be generated before all else; but… something which is not coming into existence but actually exists must in every case have been already moving before the inception of the thing [generated], and another again before that… And since genesis cannot have been the absolute first (for if so all moving things would be perishable), it is clear that neither can any of the movements next in order [increase and alteration] take precedence, since they are all subsequent to genesis.”  Physics VIII, 7 (261a 13)

[3]  In I De Caelo, Prologue

[4]  “The perfect… is prior to the imperfect… in nature, in ratio and in time… Circular motion, therefore, must be prior to straight motion.”  In VIII Physics, Ll. 14-19

[5]  I am using the language of Logic here analogically.  An ‘inferior’ in Logic is that of which a term is used as Socrates is an inferior of the term ‘man’.  How the Universe Operates, Ch. 4, IV

[6]  In I De Caelo, L. 18, n. 7

[7]  Ibid, Ch. 4, III, iii