Aisho (Compatibility) (相性)

Aisho refers to the compatibility of qualities and characters between two or more people. By further extension, when speaking of machine parts, 'aisho' is sometimes used to say if the combination of the parts is good or bad.

The origin of the word
Aisho was originally derived from the part of the philosophy of Onmyo gogyo (Yin-Yang Wu-Xin), which explained that when the attributes of all things influence each other in a good way, they become stronger; when they balance out the good qualities in each other, on the other hand, this invites bad situations. To put it shortly, the idea is that when fire and wood are combined, the fire gathers strength and produces a high level of heat, but when fire and water are combined, not only the water evaporates, the fire loses its momentum.
The actual idea is much more complicated; nonetheless, the relationship, in which things, such as four elements, influence each other and this then leads to a consequence, was expressed with a term 'aisho.'
At a later stage in history, it was used to refer to the relationships between people. Especially in the philosophy of Onmyo, it is not hard to imagine that term was applied to various aspects of things including the relationship between men and women, which are considered to be of opposite elements.

Aisho in terms of the human relationships
In the modern times, the philosophy of Onmyo gogyo is not much cared for in general; simply, when the mutual relationship between the elements or attributes of people develops to a desired direction, it is said to have a 'good aisho,' and when the combination may produces an undesirable result, it is said to have a 'bad aisho.'

In such a case, 'aisho' is placed importance in terms of various human relationships such as the relationship between lovers and the relationships concerning the organizational roles including those between the boss and the subordinates and between co-workers, as well as the relationship between friends. However, the characteristics of individuals are varied, and depending on the combination, different mutual effects are produced. Even in similar cases, the result can be greatly different depending on the situation; this is not something which can be predicted beforehand. In most cases, when someone is said to have a 'good/bad aisho' with another person, it expresses the result of an already established relationship. For example, as a result of getting to know each other as lovers, two people consider themselves compatible by taking into account both the good and bad qualities in each other and decide to get married; or one always gets nervous in front of a certain boss, and because of it, cannot bring a good result and gets scolded all the time; or one cannot help reprimanding a certain subordinate because of his/her attitude; or one always has great conversations with a certain co-worker, but not with another.

In this type of aisho, the nature of the relationship between the given people is often fundamentally different from that of others even if this cannot be explained rationally. The so-called 'love at first sight' (when one is attracted to someone without even knowing him/her) or 'getting under one's skin' (the emotion of frustration and anger that is suppressed (psychology) and continual) are the situations which are controlled by emotions inexplicable to the one experiencing it, and as a result of which causes one to feel that he/she has a good/bad aisho with the given person.

Fortune-telling and aisho
Generally speaking, aisho has an aspect which 'cannot be discovered unless one actually has a certain degree of closeness to the person.'
However, it cannot be denied that, as social animals that cannot exist outside the social relationships, humans have desire to know it beforehand; as such, often there is a tendency in us which tries to know the compatibility with others in advance.

The so-called character diagnosis also has such an aspect, and the fortune-telling which predicts the compatibility with a certain person is more popular and common sphere. The fortune-telling is based on a theory which is not necessarily logical, which is to say unreliable; however, it has an aspect as an entertainment and it is popular among people. Not to mention the character diagnosis, character grouping by blood types (or fortune-telling by blood types) and horoscope, there is even toys such as a 'love-tester'; there are many activities and commercial products related to predicting aisho.

An activity like magic also often deals with the idea of aisho.

Aisho of computer parts

It refers to a phenomenon in which, because of the combination of parts which have not gone through the operation verification, the operation of a personal computer (PC) becomes unstable or the PC cannot be activated.

The PC stops during the self-test after the power is switched on.

It either stops or restart when the PCI is initialized.

Although it can be activated, it freezes when a certain procedure is operated.
(It looks as if it stopped.)

Although it can be activated, it restarts when a certain procedure is operated.

The above mentioned are the major phenomena, and their causes can be:
The lack of power which should be supplied to each part.

Competing interruption requests. Competing memory addresses (IO). Nonstandard device drivers.

And, it is also possible that some operating parts and drivers are the cause and when the computer falls into such a state, it is often better to change the configuration rather than trying to solve the problem.

This is a phenomenon which happens basically because of differences in features and basic structures as a result of misreading of common specifications. However, this is an 'incomprehensible inconvenience (competing)' from users' point of view and the adjustment of the problematic parts is extremely difficult, not to mention understanding the cause of the problem.

The background of the case when a user is told to 'just buy a new one' is the idea that 'because the causes of the problem can be infinite, it is actually cheaper to buy a new one rather than spending time to specify the problem, even though the cost of the computer itself is wasted.'
It is better, however, to check if the individual parts operate normally at a shop where the computer was purchased as there is a possibility that it is a defective product.

On the other hand, vicious dealers might falsely blame the problem as 'the problem of compatibility' even if it was a defective product in the first place. For the people involved, this can said to be a 'black hole' even when it is compared to/dev/null.