Chemistry is really weird if you stop and consider it. The basics from the bottom up, those fundamental constituents, protons, neutrons and electrons, have the properties of charge, mass and spin and presumably exist in a good state at STP (standard temperature and pressure) or otherwise. In other words, they will have none of the properties, apart from mass, associated with any of the properties linked to the chemical elements (like being apart from a good, liquid or gas at STP (standard temperature and pressure); having colour;Given those elementary particles, in the event that you begin to pile them up, well charge plus charge equals a greater or lesser overall charge; mass plus mass equals more mass; spin plus spin - well I'm not sure spin is a property which can be added or subtracted.If it could be so arranged, but we'll ensure it is so since this can be a thought experiment, a baseball-sized collection of electrons or neutrons or protons at STP would obviously have mass, and lots of electric charge in the case of protons and electrons. But what would the colour be? What would it taste like? What would it smell like? What would it not feel like? These are unanswered and probably unanswerable questions.But assemble these fundamentals in various combinations and suddenly you do get all of the elements with their associated colours and tastes etc. That is clearly a bit weird for starters.How many atoms of gold (for example but any other element would do) have to get together or be assembled before you have the properties of gold? It surely has to be several atom worth surely.But even weirder is when you begin to combine the various elements with associated properties into molecules which have properties totally unlike the parent elements. You have hydrogen and oxygen as dry gases at STP that make water that is wet and liquid at STP. Silicon is really a solid at STP and Carbon is a solid at STP, and Oxygen is a gas at STP, but Carbon Dioxide is a gas at STP whereas Silicon Dioxide (sand) is really a solid at STP, yet Carbon and Silicon are like mother and daughter with regard to similarity. You then have Chlorine, a poisonous yellow gas at STP, and Sodium, that is a solid shiny metal at STP, and volatile enough such that in the event that you swallow any you will really do yourself a very serious mischief. However, Sodium Chloride is merely pure table salt and a compound your system requires to survive and thrive!Carbon isn't a poison, Oxygen you can breathe, but you'd die in a pure Carbon Dioxide environment, as well as in a pure Carbon Monoxide environment.Most of chemistry is deterministic and predictable, both inorganic and organic, with the apparent exception of brain chemistry, which I'll get to shortly.You'd think chemistry would be straightforward, but chemistry can act in rather weird, even unpredictable ways. I mean, assuming you have an atom of Sodium and an atom of Chlorine, you get a straight-forward molecule of table salt (salty). For those who have two atoms of Hydrogen and something atom of Oxygen you get, in a straightforward fashion, a molecule of water at STP (wet). Combine Carbon, Oxygen and Hydrogen in a particular way and you get sugar (sweet). Another arrangement can give you chlorophyll (green).Now how is this weird? Well, the basic constituents, protons, electrons and neutrons aren't salty, wet, sweet or green. Sodium and Chlorine atoms aren't salty; table salt is salty. Oxygen and Hydrogen atoms aren't wet at STP; water is wet at STP. Carbon, Oxygen and Hydrogen atoms aren't sweet; sugar is sweet. The constituent atoms comprising the chlorophyll molecule (Carbon, Oxygen, Hydrogen, Nitrogen and Magnesium) aren't green; chlorophyll is green.Just how do the properties of saltiness, wetness, sweetness, greenness, arise from those constituents that don't have those properties? It's not quite as strange as getting something from nothing or something happening for no reason at all, but nevertheless IMHO something's screwy somewhere. And enigmas like all of these lead back to that most fundamental of all issues - what's reality?Or take another case - Carbon. You'd think Carbon is Carbon is Carbon, but no. Carbon could be charcoal or coal; Carbon can be graphite; Carbon can be a diamond. The various properties of these substances, all just Carbon, drastically differ. Chemistry is definitely weird.Let's re-ask the question: How do properties (like charge, spin, mass or presumably being either a solid liquid or gas based on the method that you vary temperature and pressure) that matter (just like the fundamental particles, the inspiration of atoms/elements, subsequently the building blocks of molecules/compounds) has, morph into properties that only some kinds of matter have, like sweetness, transparentness, hardness, colour, malleability, etc. or properties drastically different from their constituents - like two gases making a liquid.I'll just note here that while the fundamental particles, the atoms/elements and molecules/compounds have specific properties, composites like humans usually do not. The human body for example is collectively a solid, a liquid and a gas. Actually I don't even have a tendency to think of the body as an organism but rather a colony composed of billions of micro-organisms, both the cells that make you up in addition to those other microbes your body plays host to. But that's an aside.Speaking of the body, the body (including the brain and therefore the mind) is one huge chemical processing factory. What goes into is not the same as what comes out!In terms of the most of one's bodily equipment, your system chemistry is pretty damn deterministic. You breathe in Oxygen and out should come Carbon Dioxide. In the event that you eat X today, your digestive juices process it in the same way as once you ate X the week before. You expect your liver chemistry to detoxify those beers you'd with the boys yesterday evening. Invest the medication, whether it is prescription or self prescribed, you depend on the truth that X + Y = Z yesterday, today and tomorrow. If your doctor prescribes various blood and/or urine tests, there's an exceptionally high amount of expectation that the outcomes of these tests will exhibit enough absolute certainty for the physician to then follow-up on, and you will trust that follow-up.The brain is just a soup vat of chemicals, organic chemicals and bio-chemicals, but chemicals yet. Therefore everything rooted within the confines of the mind is rooted in chemistry.But it is absolutely amazing what chemistry can accomplish when it is part and parcel of your brain chemistry. Things don't seem quite as deterministic then. The human brain chemistry holds sway over your sensory inputs, memory, desires, emotions, creativity, etc. and we know that those types of attributes in humans can be pretty unpredictable.Still, perhaps one afternoon you smell (sensory input) the next door neighbour's southern fried chicken cooking which in turn triggers off a whole potful of internal responses, all triggered subsequently by your brain chemistry. The chain reaction might start by suddenly feeling hungry (desire) then remembering (memory) that frozen chicken you have in the freezer and how it has been quite a while since you had a good finger-lickin' chicken dinner but you will need to pop into the corner store to get some of those 57 herbs and spices. But then you get an inspiration (creative thought) to stuff the chicken as you'll a turkey and forgo the Colonel's secret recipe, even though you get all teary-eyed (emotions) once you recall how your spouse proposed for you at your neighborhood KFC outlet following the senior prom: all that from what's basically just chemicals doing their chemical thing.If you recall something (according to the above example), presumably matter and energy are interacting since there's no such thing as a free of charge lunch. You do not get something, in this case memory recall, for nothing - free to you. But how can chemistry result in memory? Chemicals are products. Chemical reactions (those matter-energy interactions) produce new chemical products. Does that make memory a product (and ditto all those other nebulous mental 'products' like emotion, desire, morality, and creativity)? Computer memory recall isn't chemistry of course - there aren't any chemical reactions going on in your personal computer - but instead physics (energy expenditure moving electrons around, etc.) Anyway, laptops (up to now anyway) don't possess those other nebulous human (and animal) traits like emotion, desire, morality, and creativity that are presumably chemistry driven. But there's more to the anomalies of brain chemistry that just equating a memory or creativity with a chemical, if in fact the two can be equated at all.Actually I cannot accept the proposition that a molecule (however complex) can equal a memory or be a new creative idea. There should be trillions and trillions of unique memories and creative thoughts (that probably become memories) stored within the brains of the collective of human and animal societies, yet that number would vastly outnumber the possible combos of types of molecules available. It would appear that there needs to be more to memory and creativity than simply chemistry - it would appear so, but could it be so?How is it that one could 'train' the human brain chemistry to wake you up at a particular time - no alarm clock - and it doesn't matter what time you visited sleep and just how many hours of sleep you truly had? How could it be your brain chemistry likes one little bit of music but not another piece, or tips on how to turnoff liking a particular little bit of music that used to be your favourite, or type of food, or kind of animal - the list is endless. How do your brain chemistry remember X 1 day, but not the very next day? Presumably that creative thought you had today could have been considered yesterday but wasn't - same brain, same chemistry (apparently), different results. How does your chemistry-driven feelings for the better half change over time? How come the human brain chemistry can lead to sexual arousal from viewing one image however, not from another image? And it's really not just human brain chemistry either. Given seemingly identical circumstances, my cats will not necessarily perform identical actions. I'm sure you will find a logical chemically driven deterministic explanation, except that it is all so complex and interwoven that it offers more the appearance of indeterminacy and free will. If 99.99% of chemistry is deterministic, I'm sure brain chemistry will prove to be also.Science librarian; retired.