According to the Oxford dictionary:
Economics -
“1. the branch of knowledge concerned with the production, consumption, and transfer of wealth”
“2. the condition of a region or group as regards material prosperity:he is responsible for the island's modest economics”
Logic -... “the systematic use of symbolic and mathematical techniques to determine the forms of valid deductive argument...”
Noble - “having or showing fine personal qualities or high moral principles:the promotion of human rights was a noble aspiration”
A lioness will protect her cubs -up to the point where her own life is threatened. This is logical; she can always have more cubs. Abandoning her cubs to save herself is not Noble.
It really doesn't matter whether 'they' teach logic, Riz; some people just don't get it.
Riz:
“Firstly, this is a mathematical expression.”
Riz:
“Even as a mathematical expression it doesn't make sense.”
Ergo, it is not in fact a mathematical expression. It is an exercise in logic.
An apple, minus an orange, is still an apple. (a-b=a)
Oil, burnt for energy, is no longer oil. (a-b=0)
A wave, -if the energy is extracted at the 'crash'- is still a wave (until it dies a 'natural death'). And there will always be more waves.
Riz:
“Is completely beside the point. The point is that fossil fuels are 'cheaper'”.
No Riz, they aren't. And logically, they can never be.
If a group of people decide to go on a trip worth $100.00 each, and decide to put down a $75.00 deposit in advance so they only pay $25.00 on the day, they haven't saved $75.00
We don't have to spent more than $44 billion to protect waves. We don't have to spend the very best part of a trillion dollars on the military conquest of the wind (before we even build a windmill).
Using a valuable resource to depletion can never LOGICALLY be cheaper than using a irreducible resource.
Logic. Why don't some people get it, no matter how they are taught?

"Abandoning her cubs to save herself is not Noble."
-Grim

I didn't say it was. I've never said that logical action is necessarily noble. I said that the study of logic is necessarily noble. Not because it shows 'high moral principles', but rather because it shows 'fine personal qualities'.

"Ergo, it is not in fact a mathematical expression. It is an exercise in logic.
An apple, minus an orange, is still an apple. (a-b=a)
Oil, burnt for energy, is no longer oil. (a-b=0)"
-Grim

Except if you'd studied symbolic logic, you'd know that you can't use 'a' to mean an a apple and oil, and 'b' to mean an orange and combustion in the same exercise. It doesn't work that way, and just causes confusion. The nice thing about logic is that you can write logical expressions in short-hand with symbols, or in long-hand so everyone understands your argument. I'd suggest you stick with the latter until you have a proper grasp of symbolic logic.

"No Riz, they aren't."
-Grim

Well, according to Wikipedia, coal costs about $28-38/KWh. The cheapest renewable I could find was hydro, at $55/KWh. But yeah, I can see how you'd think that means fossil fuels are more expensive. If you're an idiot.

"Using a valuable resource to depletion can never LOGICALLY be cheaper than using a irreducible resource."
-Grim

Very well, if you insist (you're actually wrong, but I can't be bothered explaining the finer points of logical possibility/necessity to you, as you're apparently too slow to understand it anyway). It is quite apparent, however, that it can be ARITHMETICALLY cheaper to use non-renewables over renewables (unless the powers that be have decided 55 < 38, which seems unlikely). And when it comes to paying their power bill, folk tend to rely on arithmetic rather than logic.

"Logic. Why don't some people get it, no matter how they are taught?"
-Grim

I really wish I knew.

"Not because it shows 'high moral principles', but rather because it shows 'fine personal qualities'."
No it doesn't. It merely shows an interest in logic. There is absolutely no reason to suggest anyone interested in logic must have 'fine personal qualities'. As a general, Hitler would have been interested in logic, and all dictators interested in 'ethnic cleansing' would justify their actions on the basis of logic. Logic is a tool, just like a spade or a gun. It is only the application which determines it's moral content.
"Except if you'd studied symbolic logic...blah, blah."
This is a logical expression you could plug into any spreadsheet.
IF(a-b=(0a)),"TRUE"; where 'a' is the set of all energy sources, be they chemical, nuclear or 'natural'-irreducible, and 'b' is the total extractable energy, which subset makes the statement work? Chemical, yes; Nuclear, yes; natural, no.
"...in long-hand so everyone understands your argument." Yes I tried that first, remember, "If you have your cake and eat it..." Apparently it was too complex for you.
I have pointed out twice now that pricing is arbitrary, depending on accurate costing and subsidies. Clearly you need to check your Oxford dictionary for the word 'subsidy'.
Let me guess. You can't understand what all the fuss is about in America concerning Obama's health policy, can you? After all, it will be free, right? Free < 1, so who would argue against 'free' health care?
I congratulate you in advance, Riz. You will have the last word on this one.
You have managed to bore me.

"I congratulate you in advance, Riz. You will have the last word on this one."
-Grim

Yes, I will, 'coz you just demonstrated the validity of Godwin's law:

"As a general, Hitler would have been interested in logic, and all dictators interested in 'ethnic cleansing' would justify their actions on the basis of logic."
-Grim

And thereby conclusively proved yourself an idiot and handed the argument to me on a silver platter. Yay me.

But just for the record:

"There is absolutely no reason to suggest anyone interested in logic must have 'fine personal qualities'."
-Grim

Yes there is - it's tautological. An interest in logic is a fine personal quality. 'Fine personal qualities' does not necessarily refer to morality, which is why it is possible for folk to have the fine personal quality of an interest in logic and still be an immoral genocidal maniac. And why you can be a decent, upstanding and moral chap with the ufortunate personal quality of being a halfwit.