The topic of philosophy is treacherous due it's non-formulaic nature. Natural language is tricky on itself and using it to describe something scattered around such high layers of the Abstraction leads to the great amount of confusion. We systematically fall for even the most obvious language traps, especially during real communication. Our perception of words is highly ideological, and often ignores the substance in favor of Syntax, "reputation" of the word. Often it's okay, we can view it as semantics being replaced with Syntax and everything moving a layer further up the Abstraction. Not good, but not preventable either. But since the higher levels are less stable, it is crucial to try and stay as low down the Abstraction as possible, keeping all the semantics intact.
The word "philosophy" here is used as a generalized term that refers to the process of guessing, exploring, understanding various sections of reality driven mostly by one's own thought process. In it's most primitive form philosophy would be just staying inside and guessing how the world works without receiving any cognitive input from it. After exploring a little what a human mind is, it becomes obvious that such activity will not bring any significant results in terms of exploration. A certain amount of already processed data, an experience, is required for one to be able to make assumptions and visualize non-perceivable structures, the Syntax of the world. Syntax, because this method is mostly applicable when exploring systems that exist inside the Abstraction. Semantics are explored mostly utilizing scientific methods, though quite many details and principles of nature can be discovered just with enough resourcefulness and imagination. The main application of philosophy however is, again, the exploration of syntactic systems surrounding us. This is what can be called anthropology. This can prove to be quite a rewarding activity, since if done right it constantly gives the explorer a certain feeling of revelation, "cracking the code" and understanding of the ways to manipulate said systems for own gain. It's important though, when seeking prac tical knowledge, not to wander to far up the Abstraction. A big part of existing philosophical knowledge is just a chewing gum for one's brain, mind gymnastics. Such systems can be analyzed to train one's cognitive abilities, abstract thinking. This is quite a practical skill, but the substance of said systems is usually not valuable, and often can be damaging for one's perception of reality due to it's preoccupation with syntax. These systems, unavoidable as they are, are one of the main reasons humanity is now almost complete devoid of semantics.
This term is used to apply the concept of abstraction as it is used in CS to the world in general. The Abstraction exists as a consequence of rising complexity of social organization. Everything that exist outside of the Abstraction is almost pure semantics, while everything in the Abstraction is Syntax to some degree. Just like software, the higher you are in the Abstraction, the more dependencies you have. The more individual is "involved" in the Abstraction the more reliant he is on the framework of civilization. This interpretation is quite trivial, but the general principle remains valid. The Abstraction's "height" severely impacts it's stability. The more layers the Abstraction has the less deterministic it is.
The rules. Though found in little amounts in certain contexts outside of the Abstraction, Syntax is primarily a feature of human society. The amount of Syntax is what defines the complexity of social organization. When reaching certain amounts, the Syntax itself becomes the substance, the semantics, leading to the system becoming much less deterministic and spawning emergent behavior. The latter part is applicable to overly-complex systems in general, not just Syntax-based ones. But due to the nature of Syntax, which can be thought of as software (while semantics is hardware), over complication in syntactic systems is much more likely to occur.
Semantics is the substance of reality. It's something that really exists. It's the hardware of the world. Humans evolved in the environment of pure semantics, nature, adapting their semantics to it. Human nervous system and brain are one of the prime examples of emergency in semantic systems, our consciousness being the result of their complexity. This aspect of human nature means great amount of our life is overrun with undetermined emergent occurrences originating in the man-made syntactic systems. Reflection on this duality is what can be called existentialism.
Nervous system, complete with endocrine system, brain, organs of perception form an extremely complex machine, so complex it demonstrates great amount of emergent behavior. This is the most simple and short way to describe what words consciousness and mind refer to. We use said words to encapsulate the workings of before mentioned systems. Yet again, these words are heavily ideological and usually not used to communicate their actual substance. Our mind is just the same as any other animals, the only difference is complexity. All we do is process externally supplied data, yet the enormous number of inputs and outputs, complexity of data and inner workings of this mind-system means it's almost impossible to document or formalize it, document it as an algorithm etc. External data triggers usage of internally stored data, new data is generated from already existing data using extremely complex nondeterministic methods, a lot of different computations run in parallel, etc. But nothing comes truly from inside the brain. Everything our mind produces is replicated, mutated, processed external data. That is why experience and observations are crucial for one to partake in philosophical thinking. And the perceivable ability of our to reflect on itself can be viewed as sort of a UI, where the user is a piece of software itself, an AI maybe(Though here it's just I), but the one that runs separately from the other OS programs, and lacks the ability to communicate with them directly, forced to use the UI which doesn't grant it full control over the system, only allowing to observe and command certain processes. These