The Natural Philosopher's Guide to Science

I think chemistry so be a sub-discipline of physics and be called "valence shell dynamics".
It doesn't deserve a separate Nobel prize category any more. It is largely predictable by theory as this current prize was. Yes, the experimental discovery should be awarded too
-- A comment

You could almost hear it. The collective sigh of chemists all over the world, I mean, over similar sentiments as above. Of course as a chemist-in-training I should say something in apologia. Though as soon as I said that, I realised that the epistemological perspective of the field is nowhere found in my training. So treat this piece as what I thought I knew about chemistry at the meta-knowledge level, and why I found the aforementioned comment distasteful, to say the least.
I will begin with definitions, like all good epistemological pieces should. To be sure, physics is the study of physical things and how they behave, in other words, the physical laws. Technically then, chemistry is certainly a subsidiary of physics, but so is biology, geology, climatology and every other subject studying the tangible, because the tangible obey physical laws. Such classification then becomes useless, the field too bloated, which defeats the purpose of classification in the first place.
As such, we must recognise the two kinds of classifications here: the technical one and the utilitarian one. So, an attempt to unify chemistry under the grand umbrella of physics is technically proper but not useful. Utilitarianism here is of course anthropocentric -- Man is the measure of all things, said Pythagoras. The study of behaviours of valence electrons has implications in the chemical industries -- from paints, fertilisers, cosmetics, foodstuff, to drugs -- that are paramount to our lives that they need a separate category. This is even truer for the engineering fields, the direct spawns of physics, that the industry would benefit from clear distinctions. As important is the utility to the academic learning. The massive amount of knowledge has to be compartmentalised -- the size of the field should be roughly learnable within a four-year bachelor's degree. Imagine if a physics degree also requires you to learn chemistry to the level of the current chemistry degree -- how long would that take, and how useful is that for the learner who doesn't intend to go to grad school? And the utility values to the industry and academia are intertwined. The training during the four-year bachelor's should be at least enough for the learner to have a basic grasp of the field to start out in the industry (or his curiosity piqued enough that he would choose to go to grad school, but that's another story).
Sure, the divisive line blurs when one talks about physical chemistry for example. Does thermodynamics belong to the realm of physics or chemistry? Sticking to utilitarian value, one should resist classification then, and embrace both labels, because, why not? The separate classification of chemistry should serve to make clear; when it does not serve this purpose and potentially misleads instead, then the classification has ceased to have any utility.
In a talk I attended where Aaron Ciechanover, 2004 Nobel laurate in Chemistry, was the speaker, someone, evidently an organic chemist grad student, asked about the role of synthetic chemist in increasingly biological approach in drug industry. He gently rebuked the questioner regarding the absurdity of such division. In short, he lamented the current state of affairs where science departments are so isolatedly fragmented they are not communicating and collaborating with each other. When I think of these things, strangely enough I am reminded of Victor Frankenstein, whom Shelley described as a 'natural philosopher' if my memory serves right, and his creature. That there was a time when the hard sciences are united on a front called natural philosophy, before it has inflated to the the sewing of appendages that barely fit each other, the chimeric monstrosity it is today.
-- 
Recapitulation so far: It is of utility value to have chemistry as a separate field from physics. This argument may not apply to other fields, so I'm going to offer another argument that applies in all cases. First, if you haven't seen the xkcd's Purity spectrum, go see. Hoewever, as you might suspect, chemistry is not just applied physics, biology is not just applied chemistry and so on. You see, at some point, neuronal connections (biology), neurotransmitters (chemistry), and a bunch of other stuff, as a system, gains enough complexity to become your mind, your consciousness -- picture gestalt, that which the whole is greater than the sum of its parts. You can't go from physical laws to understanding schizophrenia because the interactions involved have become intricately, impossibly complex to unravel. Such property of complex systems is called emergence, and fields are systems of knowledge. Consequently, while you can say how pure your field is compared to to others, it doesn't make one field any more complex than the others, thus any more worthy of study compared to others.
Bottom line is: dividing sentiments are not useful. There is no point in arguing whose field is more significant. What the scientist must do is make distinctions when necessary and useful, and not make them when unnecessary and useless. Carry on that spark of lightning that keeps a burning fire inside Frankenstein's creature's heart; that keeps him alive, that leads him to search himself, that pushes him to wrestle with his creator, that makes sewn appendages move as one.

Lexical Order

If you have shelved your thermodynamics at the back of your mind, go retrieve it. Done?

Δ_fH^O 

According to the order of appearance: change, formation, enthalpy, standard. 

But lo and behold, you are supposed to read that as: standard enthalpy change of formation. How can that be?

This is because English language adopts lexical order which does not really follow natural thinking process. First off, languages can be divided into two according to the lexical order: modifier-modified and modified-modifier. English belongs to the former, since the modifier precedes the modified. Consider the phrase:

beautiful girl

girl is the noun, the modified, while beautiful is an adjective, so it is an attribute, a modifier.

In Swahili, the same phrase would be (courtesy of Google Translate):

msichana mzuri (literally, girl beautiful, preserving the lexical order)

Note that now the modified precedes the modifier.

As English speakers we probably do not realise how unnatural is the English lexical order. If you think about it, the main idea must be the modified, while modifiers are just attributes. If we are talking about a 'beautiful girl', we are talking about a girl, not a beautiful.

Our mind is usually concerned with the bigger picture first, i.e. the modified; while details, the modifiers, can be filled later. Is there evidence that this is the natural way of thinking? We write symbols that way. Again, look at the same symbol of  'standard enthalpy of formation':

Δ_fH^O 

Note that the modified is change. The main modifier is enthalpy. Thus it is a change -- what kind of change? Enthalpy change. 

Other modifiers, formation and standard, appear as subscript or superscript. f subscript is appended after change because formation specifies the type of change. (Digressing a little bit: This is the new IUPAC convention. Last time, the f subscript used to be placed after the thermodynamic state function. This is not very accurate since, as mentioned, formation is the attribute of change rather than that of enthalpy. IUPAC actually pays attention to proper lexical order!). Nought superscript is more like the modifier to the whole thing, like thus: (Δ_fH)^O . 

Having said all that though, it languages do have ways to reverse lexical order. English uses 'of' to place modifier after the modified:

girl of unworldy beauty

While Japanese uses the familiar 'no' (の), which performs very similar functions to 'of'. This though, one must admit, is kind of unwieldy. The rendering of our symbol if the order of appearance is to be followed would be:

Change (of formation) of enthalpy, in standard conditions

There is an alternative argument to the 'unnatural' argument, which is to say that the modifier-modified languages put more importance, then, in the details rather than the big picture. Language and culture are intertwined, as I wrote quite lengthily before. Language is the frame on which thoughts are built upon, so its structure will influence the product of thoughts, i.e. culture, in some ways. We can extrapolate, say, that users of modified-modifier languages are more individualistic than they are socialistic, because they are more concerned with details. This conclusion is, of course, far-fetched. However, you may be surprised that there is actually correlation of sorts: A lot of Western languages are actually modifier-modified and the Western culture tends to be more individualistic. 

But then again, as I pointed out before, you have to be aware that indeed language influences culture, but the other way is also true; the two are intricately intertwined. Like nature and nurture. Ouroboros-like.

Physics Limericks

Space
Seven steps each ten million to one
Describe the whole space dimension
The Atom, Cell’s girth
Our bodies, the Earth
Sun’s System, our Galaxy – done!

Time
The Creator, seen as Army Sergeant Major, barks out his order for the week.
First thing on Monday morning, Bang!, Light
Sun and Earth, form up, Friday night
At a minute to twelve
Eve spin, Adam delve
In the last millisecond, You, right?

Speed
A child cycles ‘round the schoolyard
Which lies on the Earth turning hard
The Earth rounds the Sun
As Sol does “the ton”
And our Galaxy flies – Gee! I’m tired

– Tim Rowett, Three Limericks – On Space, Time and Speed

Note:
Space
10⁻¹⁴ m : Atomic nucleus
10⁻⁷ m : Cellular nucleus
10⁰ m : Human body
10⁷ m : Earth's diameter
10¹⁴ m : outer Solar System
10²¹ m : Galaxy's diameter
10²⁸ m : Universe, and a bit more
Time
A week is 7 days,
Each day 2 billion years
A minute is 2 million years
A millisecond is 23 years
Speed
7 mph : A child cyclist
700 mph : Earth's rotation speed
70,000 mph : Earth's revolution speed
700,000 mph : Galaxy's turning speed
1,400,000 mph : Galaxy's speed through debris of Big Bang

I think it's really amazing that if you downscale the age of the Universe to one week, then we humans would only occupy the last minute of it (and of course Earth itself only formed on "Friday night").
Such displays of logarithmic leaps never cease to amaze. And of course, if we are talking about space dimension, the classic documentary Powers of Ten (directed by Ray and Charles Eames) comes to mind. Even though it was produced back in 1977, it is still a wonderful sight to behold. This is so famous that one of The Simpsons' episodes featured a parody of it. Sadly, it has already been removed from YouTube because of copyright issue.

Again, we are reminded of the very long scale of space, time and speed; and our tiny, insignificant place in it.

Stirling Engine

Stirling engine is a heat engine. In other words, it converts heat to mechanical energy. So you can see in the above that it converts heat from my coffee to rotational motion of the discs.
The principle is very simple. First, let's take a look at the components. There is a shallow cylinder directly above the cup enclosed by two black metal plates at top and bottom. There is a big opaque piston inside the cylinder, connected to the front pedal. At the back of the disc, there is a back pedal, which is connected to a diaphragm, which looks like a membrane.
The cylinder is airtight. As heat is transferred to the bottom plate, the air expands and pushes the piston up. This sudden increase in pressure also forces the diaphragm, which in turn raises the back pedal. Since the disc, back and front pedals are connected rigidly, when back pedal moves up, front pedal moves down, which in turn, push down the piston. Repeat.
The front and back pedals are 90 degrees out of phase so that the up and down movements mimic legs pedalling a bicycle.
So, how is that more interesting than, say, a steam engine, you ask?
The physics mechanism described above works as long as there is a temperature gradient. So it works using ice as well, as you can see below:

I'd say my spending a weekend to work on this is totally worth it.
Cool! Literally.