As we have already covered the judging functions last time, we will be discussing the perceiving functions: introverted sensing (Si), extraverted sensing (Se), introverted intuition (Ni), and extraverted intuition (Ne). The terms sensing and intuition may not sound as concrete as the concepts of 'logic' and 'ethics'. In general, sensing is the ability to process and react to the physical environment, and intuition is the ability to interact with thoughts and ideas.

Usually, the perceiving functions are not as straightforward to tell apart compared to the judging functions. However, by using the static / dynamic dichotomy, we can find the differences in comparing these four functions. The static and dynamic dichotomy describes a degree of volatility of one's thoughts and decisions. This is seen on a behavior level the ability to assert their stances with minimal influence from the environment, or the tendancy to shift to different gears according to the current circumstance.

The dynamic functions are the functions that can react swiftly to changing internal and external demands, and this includes the extraverted judging functions (Fe, Te) and the introverted perceiving functions (Ni, Si). The extraverted judging functions are heavily characterized by attempts of influencing and being influenced by surrounding factors. For example, Fe adapts to the surrounding emotional atmosphere and contribute to maintaining the harmony as well as proper social etiquette, while Te engages in accumulating knowledge and impose fairness and efficiency.

The static functions, on the other hand, will typically establish a mentality that resists abrupt change in decisions before fully encompassing external factors into their decision-making. This includes the introverted judging functions and the extraverted perceiving functions. The introverted judging functions make decisions according to their own judgments, which are either backed by their own moral compass (Fi) or acknowledged principles (Ti). This does not mean that static functions do not factor in surrounding parameters, but rather, values a certain level of consistency in their thought processes. For example, Fi users have their "own way" of treating others that might diverge from the social norm, and Ti users have their "own set of rules" they abide by that may not always match external demands.

With the concept of static / dynamic functions introduced, we can list out the four perceiving functions and the differences between each of them. Below are the descriptions I have for each perceiving function to the best of my knowledge and explanations:

Introverted Sensing (Si)

Introverted sensing is the cognitive function that tries to achieve a certain level of physical harmony. Some might regard this as a sign of being lazy or slow. But rather, this function enjoys polishing the details in their doings instead of making abrupt and hasty decisions just to get it done. This function is often associated with being risk-averse and promoting a restful, peaceful, and simple life, and therefore choosing to commit to fewer activities. As uneventful as one might think their lives might seem compared to an average person, each activity they commit to tends to be very detail-oriented. It is easy to see an Si user slowly trying to accomplish one project they care about, and eventually build something impressive due to its extreme perfection in the details. Introverted sensing is a dynamic function as it gives off a 'whatever' kind of vibe and let events develop on their own without any certain direction, and the directionless element brings about the flexibility in adapting to external parameters.

Extraverted Sensing (Se)

Extraverted sensing is the cognitive function that attempts to actively change the surrounding environment to achieve a certain goal. It is often manifested as the need for force, power, and aggression. Se users are often seen as restless and ambitious. Extraverted sensing focuses on narrowing down the number of items on the to-do list and execute it, and as a result being very quick and decisive about short-term decisions without too much consideration of the details so that with each decision they make, they can achieve their ultimate goal. This is a static function as it features a high level of assertiveness to ground decisions in place and focuses on executing the decision and reaching the goal, regardless of the environmental factors.

Introverted Intuition (Ni)

Introverted intuition is the cognitive function that focuses on the development of the inner working of the mind and the flow of thoughts. This function factors in time and lets thoughts flow in the mind to reach a certain conclusion, regardless of its sound logic. Therefore, this function often manifests as thinking out loud about a certain thought that may easily fall off tangent of the current scenario and therefore brings about fantasy stories and the "cutesiness" that is usually non-realistic. This function can come up with so many scenarios in the mind that it results in an individual being indecisive, the merit of having introverted intuition is that given some parameters, the function can produce a possible scenario of how "it is going to play out in the long-term". Introverted intuition is a dynamic function in that it lets the thought grow directionless like bean sprouts growing out of a flower pot — the thoughts can be in any shape possible and can keep extending in any crazily irregular shapes without limit, and hence comparable to fantasies that are not bounded by reality.

Extraverted Intuition (Ne)

Extraverted intuition is the cognitive function that focuses on the development of connections between ideas. This is less focused on the development of each thought, but connecting the individual thoughts so that they form a map of thoughts that can respond quickly to new ideas. The processing of input data from the environment will be "fitted into the big picture", and therefore Ne users are often seen as innovative "big picture people" and constantly zoom out of the current thought to find new ideas outside the box to support and construct their thoughts. Extraverted intuition is a static function in that it attempts to produce a network of thoughts grounded by the connections itself. This is physically comparable to a bird nest, where it can grow in size and firmness by adding the number of twigs to the nest itself and expand, but it is still and will always be called "one bird nest" due to the persistence of its "nest shape".