Chapter 20 That in creation there is no succession (alternate translation)
 It is also clear from the foregoing that all creation is without succession.
 For succession is proper to movement: while creation is not a movement nor the term of a movement, as change is. Therefore there is no succession therein. See also argument 4 below.
Notes Creation, in other words, is the beginning of time. Or, put another way, time is defined as succession. This is why it is improper to speak of what happened “before” creation. There was no before.
 Again. In every successive movement there is some mean between its extremes: for a mean is that which a continuously moved thing reaches first before reaching the term. Now between being and non-being which are as the extremes of creation, no mean is possible. Therefore there is no succession therein.
Notes Shades of the fundamental theorem of calculus here? Let he who readeth understand.
 Further. Every making that proceeds by succession must needs take time: since before and after in movement are reckoned by time. Now time, movement, and the thing subject to movement are all simultaneously divided. This is evident in local movement: for that which is moved with regularity passes through half a magnitude in half the time.
Now the division in forms that corresponds to division of time is according to intensity and remissness: thus if a thing is heated to such a degree in so much time, it is heated to a less degree in less time. Accordingly succession in any movement or making is possible according as the thing in respect of which there is motion is divisible: either according to quantity, as in local movement and increase; or according to intensity and remission, as in alteration.
Now the latter occurs in two ways. First, because the form which is the term of movement is divisible in respect of intensity and remission, as when a thing is in motion towards whiteness: secondly, because such a division happens in dispositions to such a form; thus the becoming of fire is successive on account of the previous alteration as regards the dispositions to the form. But the substantial being itself of a creature is not divisible in this way, for substance cannot be more or less. Nor do any dispositions precede creation, since there is no pre-existing matter, for disposition is on the part of matter. It follows therefore that there cannot be succession in creation.
Notes Take “that which is moved with regularity passes through half a magnitude in half the time”, which is non-relativistically true. But it doesn’t matter if it’s relativistically false, because the main point is that the movement is reckoned by time. And did somebody say evolution? The intriguing point is substance cannot be divisible. Thomas is speaking of creation ex nihilo, of course, but it’s interesting to consider the definition of species (biological, not metaphysical) in this context. One species does not share the essence of another, even though they share material aspects. One to another there is a strict demarcation, a gap.
 Further. Succession in the making of things results from a defect of the matter, that is not suitably disposed from the beginning for the reception of the form: wherefore, when the matter is already perfectly disposed for the form, it receives it in an instant. For this reason, since a diaphanous body is always in the last disposition for light, it is actually illumined as soon as the luminous body is present: nor does any movement precede on the part of the illuminable body, but only local movement on the part of the illuminant, which becomes present.
But in creation nothing is required beforehand on the part of matter: nor does the agent lack anything for His action, that may afterwards accrue to Him through movement, since He is utterly immovable, as we have shown in the First Book of this Work. It follows therefore that creation is instantaneous. Hence in the same instant a thing is being created and is created, just as in the same instant a thing is being illumined and is illumined.
 Hence divine Scripture declares that the creation of things took place in an indivisible instant, when it says: In the beginning God created heaven and earth: which beginning Basil expounds as the beginning of time, and this must be indivisible as is proved in 6 Phys.
Notes Recall the “utterly immovable” meant unchangeable, metaphysically simple, constant. Creation is instantaneous! Ain’t you amazed, as Captain Aubrey would say? Everything there is—everything material+energy, that is—all at once. Meditate on this and try and imagine—for this is all you can do: try—what kind of power this requires. Yet another reason to fear God, where I use that word in its old sense.
Categories: Philosophy, SAMT
Creation, in other words, is the beginning of time. Or, put another way, time is defined as succession. This is why it is improper to speak of what happened “before” creation. There was no before.
This is conflating the concept of time with ways of measuring it. Of course there is a before the Universe just as there is a before any given event . What you apparently mean is that the measurement of time began with Creation. What else does ‘eternity” mean except infinite time?
Dav the start of the universe is a singularity. What is south of the south pole?
Does space exist beyond the tool used to measure it? For example, does it stop at the edges of a ruler? If not, why should time cease to exist where it can’t be measured?
To answer your question, on a globe nothing although the location of the south pole is rather arbitrary. That it coincides with the rotational axis is convenience and nothing more. What is south of the south magnetic pole? If it’s a point on a map on a planar surface then south is everything below that pole albeit not on the map.
South is a direction. The values we assign to time are measurements along a line defined by time. Just like the values on a number line. Other than forward and backward (i.e., preceding and following) there’s no inherent direction to the measurements just as there is no direction to the values on a number line. Lines are infinite. Complete lines don’t have being/end terminals although line segments do.
Day, to measure anything you must first have the laws of nature.
Without the universe you do not have the laws of nature.
to measure anything you must first have the laws of nature.
Er. Maybe. But what I’m complaining about. Time didn’t suddenly start at Creation but its measurement did. Just because something can’t be measured doesn’t mean it doesn’t exist or the problem is moot. Is x < 0 an improper statement? How is this different than saying t < 0?
But time just is the measure of motion in mutable being. It is not itself a substance. As Einstein put it, “Formerly, people thought that if matter disappeared from the universe, space and time would remain. Relativity declares that space and time would disappear with matter.” To reverse the direction, we would say that space and time would also appear with matter.
“[T]here are no objections of principle against the introduction of this hypothesis [general relativity], by which space and time are deprived of the last trace of objective reality.”
— Albert Einstein, “Explanation of the Movement of Mercury’s Perihelion on the Basis of the General Theory of Relativity,” 1915
DAV: Time didn’t start at creation, its measurement did? That doesn’t make any sense. If there was a “before” time started, then that was already time because you just measured it to say so, so it was by definition NOT before time started. We are talking pure metaphysics here, not any sort of actual measurement by an instrument. Just THINKING. And just thinking, it is impossible to think of a point before time existed, because to think it, you are measuring it. All you’re talking about is measuring or not measuring something that exists, like picking a date and saying “we measure from here and nothing else before it counts.” But time WAS before that point, whether you count it or not.
If you want to posit that time is infinite, you can. But that implies that matter is also infinite, and space is also infinite. They all either exist or they don’t.
YOS, so Aquinas, being well-versed in general relativity, was able to use this definition of time and wasn’t just rigging the results with his definitions?
Time didn’t start at creation, its measurement did? That doesn’t make any sense. If there was a “before” time started, then that was already time because you just measured it to say so, so it was by definition NOT before time started.
Not at all. I haven’t made any measurements I’m saying there was a time prior to my reference event. What exactly did you think I measured? So how long has God been around? Always? What does that mean?
But that implies that matter is also infinite, and space is also infinite. They all either exist or they don’t.
How do you know they are not infinite? Just because you can’t imagine it? It just seems unreasonable? There was a Big Bang therefore Nothing preceded it? How do or would you know?
Surely he could arrive at the truth through other means.
BTW, eternity is not infinite time but timelessness.
Timelessness is stasis. Time is a measurement that requires change to acquire.
Time is a measurement that requires change to acquire.
IOW, it requires a material universe and cannot exist without it, as Einstein averred.