i mean, as time goes forward, irreversible proceses increase global entropy, and these are the interesting processes...

rlumley, there's also enthalpy as a major driving force of change. It often works against entropy, and then temperature is usually the factor determining which one "wins" out.

orathaic, obviously the argument that evil need not exist can only be made under the assumption of a benevolent all powerful all knowing God. The arguments you make are for the universe as is, but given such a God, it need not be the way that it is. I mean, once you posit such a being, all bets are off. I would never make the same claim if we were arguing on non-theistic grounds, and I otherwise share your views. I find that evil, suffering, and pain are quite easy to explain when the universe is viewed through a non-theistic lens. By arguing that they need not exist given an omnipotent, omniscient, and benevolent God, I simply hope to make it plain that it is not so easy to explain the existence of evil, suffering, and pain in such a theistic context.

@ Chrisp: I'm a chemical engineer, I know my thermodynamics. :-)

You can think of enthalpy as potential negative entropy. That's really all it is. Because to create that heat, you had to burn something, which increased entropy.

@rlumley - by training i'm a physicits, and so i didn't spend much time thinking about enthalpy (i think my comments here have made this lack of understanding obvious), so i'd love for you to illustrate that point a bit more.

@Chrisp - I am argueing from a non-theistic position, not an atheistic one, but i don't see how any theist can tackle these philosophical questions without taking into account observations of the Universe (especially if they understand that to be God's great work)

It's clear how the world works, but if you believe in God it is not clear how God works. You can however easily construct any model of God to fit observations. If you have an arbitrary concept which can be defined to suit yourself it should be pretty easy.

That is assuming you want to build a theism on reality (rather than assuming our understanding of reality is flawed and perhaps some kind of deception which God has put before us as a test... maybe we are all in some kind of 'matrix'-like machine - but unfortunately that kind of reasoning doesn't help us find any answers - it just leads us to question whether the 'higher' reality might be a similar simulation... and if so when do you stop asking what is Real..) So assuming this is The Reality (which is you are a theist is also God's Creation) then observation can tell us a lot, including about the challenges we face.

Being able to identify 'evil' is a useful trait. It is the gift of knowledge - that God gave us but to no other animal (at least from the Christian view-point) being able to do evil is a consequence of free-will, i suppose if we are made in the image of God that means we are free morale agents - thus to be truely like God we must be capable of evil. Now God may in fact be perfect but we know humans are flawed - thus some will commit evil acts. There is no other way to make us 'free' while still making us.

Is that enough to justify our own evils? As for natural disasters, i'm not sure, i know i saw a Muslim geologist explaining how earthquakes cause tSunamis and then go on to explain that God was punishing people... Perhaps someone who actually believes in the Judeo-Christian God can explain it.

Yeah, you're right rlumley. Are you a chemical engineer now? Or a student of chemical engineering?

orathaic, I know what you mean, but you're arguing that evil exists because of the way the universe is, and I would then argue, why is the universe the way that it is to allow evil, given that the omnipotent, omniscient God that was responsible for it's creation is supposedly benevolent. I don't mean to argue philosophical skepticism, I just don't see a satisfactory answer so far that evil would exist if such a God exists. I mean, it's pretty clear that pain and suffering do exist.

Being able to identify evil is only a useful trait when evil exists to be identified.

true true... ok i guess the type of Universe which exists does limit the possible features of this God thing; but i've always studied physics because i wanted to understand the greatest secrets of the Universe, and i think any light it can shed on 'God' is interesting, maybe even enligthening...

am i supposed to tell others what i've come to grasp or can they decide for themselves without any preachy-ness?

I'm a chem E major, going into my third year. But the major is technically Chemical and Biomolecular engineering - I'm on the biomolecular side and am Pre-med.

@ Orth:

To which point are you referring?

*And I am

@Rlumley: this was the point to which i was refering "You can think of enthalpy as potential negative entropy."

OK. I'll try to respond when I get some time at work today.

@ Orth:

Energy (enthalpy) is really just a way of storing used entropy.

Consider the following: We've got some heat source that's provided some enthalpy to drive some reaction that leads to an overall decrease in entropy. Everyone agrees this can happen, and it does all the time.

But where did that enthalpy come from? Generally, we burned some fossil fuel (a massively entropic process) to generate that heat. So if we consider the entire process (Burn a fossil fuel, store the negative entropy, release negative entropy) the entire process is still an increase in entropy. And that entropy can be measured by the efficiencies of each of the processes (Burning, storing, releasing).

This is kind of tangentially related, but it's very much a way of viewing the world that I use: There is really only one resource, order. That order takes a number of shapes, but thermodynamics tells us that eventually, we will run out of order. And anytime we do anything, we decrease the amount of order in the universe, because the efficiency of that process is not 100%.

This is why I'm so opposed to blind environmentalism, and the notion that we should conserve at all costs. Because if they truly wanted to be as sustainable as possible, environmentalists would all commit mass suicide.

Well I see Thermodynamics has successfully killed this thread. :-P

hmm, i'm still confused, but the change in enthalpy can be used to determine whether a reaction is endo/exo-thermic (taking in or giving out heat)

If it is taking in heat the enthalpy increases - so this reprezents heat being stored (as in a fossil fuel) in some chemical bonds, say - so in my mind i would use the word potential energy or a system which now that i think about it just confuses me even more... there is more than just the energy stored in the chemical bonds though right?

actually since a process which keeps the enthalpy the same is where no heat is transfered and no work done by or on the system then the pressure/temperature and volume don't matter it is just the 'heat' contained in the bonds. However in some cases heat added to a system will go to increasing the pressure... what effect will that have on the enthalpy?

is H = U + pV then it will increase, right?

@chemists & physicists: I am afraid that most of this is above my head. However, I do have one question: do you really think this stuff applies to morality and the existence, or not, of God?

I think it applies to the existance of Evil, suffering and matters of nature. I don't care to comment on the existance of God.

@ Orth:

All heat has to go somewhere. It can go into PV work, it can go into entropy, it can go into making air float and convection, it can go into internal energy and vibration of molecules. But it goes somewhere. :-)

When you add heat to a system, on some level each of these changes, but usually it's minuscule.

from the point of view of the kinetic theory of gases heat is just kinetic energy of the atoms/molecules. For elastic collisions no kinetic energy is gained or lost, but 'heat' can be transfered from a faster atom to a slower one (heat flows on average to cold tings from hot things - this is an example of a process which increases entropy)

For inellastic collisions the kinetic energy can be enough to overcome the binding energy of a given molecule and allow a new one to be formed. In this case enthalpy can be increased while keeping entropy constant.

Is that correct?

Different molecules have different entropies associated with them though.

yeah, i knew it wouldn't be that simple...

and i'm ignoring vibrational modes which molecules can enter, both translational and rotational which amount to a different energy state - again here i don't know what the enthalpy orentropy difference would be.

Hm. Maybe you can help clarify this for me rlumley, since my formal physics education ended after first year university.

You've described enthalpy as requiring a heat source to drive some reaction to reduce entropy. That makes intuitive sense, but I've also heard enthalpy described as the driving force for things to move to a state of lower potential energy. I've heard the enthalpy of fusion used as an example, where water freezes after losing enough heat because enthalpy drives it toward the state of lower potential, despite it being more ordered, and therefore less entropy. The "deciding" factor being the temperature. In this case it seems enthalpy isn't so much driven by a heat source as it is giving off heat which would still increase entropy overall, but still decreases it on a local level.

The same might be said for chemical compounds to naturally tend toward their more stable configurations of lower potential energy and for matter to clump together to form planets and whatnot as a result of gravity and the drive toward lower potential energy, all decreasing entropy on a local level, but presumably increasing it overall. While I understand now that enthalpy is a colloquial representation of a couple of factors in equations, it still seems like it could be viewed as a very important driving force, since perhaps, life would not exist if it were not for the stability of amino acids and whatnot.

@ Chrisp:

Sure it's driven by a heat source: The water is the heat source. "Hot" is an entirely relative term. :-)

But we're saying the same thing in different ways. The two are not mutually exclusive.

No, I know they are not mutually exclusive, but I didn't know why that was. In what sense is hot an entirely relative term? Is not temperature the average kinetic energy of the particles, with zero movement representing absolute zero, the lowest possible temperature? If it exists on an absolute scale (I think many physicists posit an absolute ceiling to temperature as well), then its not really relative, is it? I know that enthalpy is relative, and though the two are very related, they are not exactly the same? Forgive me if I've got anything wrong.

thank you for bringing this to the table sir, it is enjoyable to witness philosophical debate, too rare in my day to day life...

Well Temperature is absolute, but it's only important in terms of relative temperatures. (In thermodynamics - in biology, absolute temperatures are pretty darn important)

In that case, the water was "hot" because it is giving off heat to the surroundings, which I suppose are pretty darn cool.

@rlumley: Rand bases that paragraph on Aristotle, like most of her argument.

Paradoxically, that paragraph is both obvious and obviously full of holes.

ok, so enthalpy and entropy - when you have an endothermic reaction (one which takes in heat) it is taking energy from it's enviroment and increasing it's own enthalpy (which is a measure of energy - which is a conserved quantity, right?) entropically speaking there is some heat source (a temperature gradient) and instead of the heat dispersing (as it usually would leading to an increase in entropy) some of the heat is absorbed by the exothermic reaction.

So the local increase in enthalpy can be seen to delay the increase of entropy - though no all of it because some heat will still disperse in most processes, and it is random (ie which molecules absorb the energy is completely random).

@adversary: i haven't read any Arisytotle, but i did read some Plato and found his arguements rather weak - while he pointed out things which he claimed were obvious i felt like he skipped many a step...

@ orth: More or less

@ Adversary: While I agree with a lot of Rand, I often make profoundly different arguments than she does - and I never rely on "Oh, Rand said it, it must be true", which is what you imply. If you'd actually point out which of my (probably thirty) posts in this thread you're replying to, I'd be happy to engage you.

@rlum: i think it was one of the Rand posts on the first page of the thread... i had to actually go back to see what you had said.

also which bits are less?

None of them. I just say that. :-)