We know that things don’t stand still in life. We change as we get older and as life teaches us new lessons. We cannot therefore expect that the person we marry will in every way remain exactly as they were on the day we met them. At the same time, we want to know that the person we marry is indeed what they appear to be and is not going to fundamentally change later on.

Focus on the fundamentals of their character

That is why it is so important that we put most of our focus on “the fundamentals.” Those are the absolutely most core parts of a person’s character. They are not only the most important elements of who the person is; they are also those features that are least likely to change. When thinking about the qualities you want in a spouse, you should give special attention to these fundamentals. While they are not immune from the normal preferences people have for particular types of people, it is best not to treat them as mainly about personal preference and more about what we know contributes to a stable and happy marriage. These fundamentals are your key.

The five most important traits affecting relationships are (in descending order):

• Emotional stability/Low neuroticism – Low in agitation, anger, irritation, hostility, touchiness, defensiveness.
• Agreeableness – High degree of niceness and friendliness.
• Conscientiousness – Making an effort for the relationship, having determination and not being fickle.
• Openness – Willingness to share, to listen, to be generous.
• Extroversion – How outgoing and loud a person is, how fun-loving and exciting.

Traits are broadly stable. This means that even if people try to hide them, they will show over time. For example, if a person has had a string of unfortunate experiences at work and had to change jobs repeatedly, this likely is not an accident and suggests a person high on neuroticism. That same person is more likely to have road rage or freak out if there are long security lines at an airport. This person will probably act towards you in the same way sooner or later.

The first three are the main ones. For those three, it is about finding someone – if possible – who is high on the positive side. While all extremes are bad, finding someone high on at least two of the first three is a real plus.

The last two are more about what to avoid. It is best to not end up with someone extremely high on closeness or extroversion, but there is no advantage in finding someone extremely low either.

The main point is that if you find someone who scores decently across these five dimensions, then you have the makings of a successful marriage. If such a person comes your way, don’t be quick to look for reasons to let the opportunity pass you by.

Here is a brief comment on each:

Emotional stability

The personality trait that affects our relationships most is emotional stability.

Neuroticism (the opposite of emotional stability) is a general tendency toward negative emotions, such as intense worry, high irritability, frequent mood swings, depression, and high anxiety. Those who lack emotional stability tend to be moody, touchy, anxious, and quicker to anger — all traits that make someone more difficult to live with. Those high in neuroticism are much more likely to have negative and argumentative interactions with others, including their partners. They also tend to be more jealous and less forgiving.

People rated as lower in emotional stability (which is higher in neuroticism) more frequently end up in relationships that are high in conflict and abusiveness. Long-term studies show that more than any other quality, being high on neuroticism – what is referred to as contrariness – is the foremost predictor of marital conflict and divorce. In fact, the results showed that people high in neuroticism were more likely to break up with partners who were low in neuroticism than with partners high in neuroticism. It seems that emotional instability enjoys its own company.

It is not the case that the higher on emotional stability the better.  Firstly, someone can be so stable but have all the emotion of an ice-block; some degree of emotional variation is positive. Secondly, people are different; many people prefer to be around people who are livelier emotionally.

Agreeableness

Some people look down upon the quality of agreeableness, but they are wrong. The “nice guy” or “sweet girl” label is rarely used as a compliment – but it should be. It has been shown that “responsiveness” was one of the strongest long-term predictors of a happy and lasting marriage. Even more than the seemingly obvious qualities such as love, affection and positivity.

Agreeable people are typically cooperative, polite, kind, and friendly. People high in agreeableness are more trusting, affectionate, altruistic, don’t belittle others, don’t cause trouble or conflict, are less rigid and don’t tend toward perfectionism. When a person is high in this personality trait, they are less me-centric and more we-centric, showing great concern for the welfare of others. They look for the common good in others, are quick to hear out opinions of the people around them, and look for harmony instead of discord.

Disagreeable people are likely to be more competitive or aggressive, have less patience, and will be more easily irked and annoyed. They care less about other people, are more likely to make offensive or disparaging comments, or to think they are better than others.

It is possible to be too agreeable. When taken to the extreme, people may allow themselves to be mistreated or not advocate for their own interests. Also, super-agreeable people are often so eager to avoid conflict that they become reluctant to take up or express their own views, making them highly uninteresting and often frustrating.

Being a bit disagreeable is necessary to create change or to achieve progress. A robust exchange of ideas is often a good thing. However, people need to understand that when it comes to marriage, where there is a high value attached to being loving, agreeableness is a definite plus.

Conscientiousness

Boring is the new exciting. Conscientiousness is about being reliable, practical, rule-following, and organized.

This may not sound like the most alluring trait, but it’s good for a long-term mate. Conscientious people tend to be more dependable and trustworthy in their relationships.

People who are less conscientious are more difficult to deal with in a relationship – they cancel plans, fail to fulfill their obligations around the house, act carelessly, and fall through on their promises. Studies have looked at people they term “novelty-seekers.” These are people who are high on extroversion but low on conscientiousness, which makes them particularly impulsive. They are likely to favor the immediate thrill over long-term consequences. This puts them at increased risk of a range of risky and confrontational behavior. Such behaviors are great at the start of a relationship, as it makes it full of excitement, but it doesn’t bode well for the long term. Besides all the trouble they are likely to court, those with low conscientiousness tend to get bored of the relationship quickly and thus offer less relationship stability. They are more likely to lose interest in a relationship because “the spark has gone.”

Conscientious people have solid determination and stick with the job until it is done. They are willing to grind things out when necessary and are more prone to make reasonable choices and decisions. When running a home and raising a family these are premium qualities.

Openness

Openness denotes receptivity to new ideas and new experiences.

People with high levels of openness are more likely to seek out a variety of experiences, be comfortable with the unfamiliar, and pay attention to their inner feelings more than those who are less open. They tend to exhibit high levels of curiosity and often enjoy being surprised.

People with low levels of openness prefer familiar routines, people, and ideas; they can be perceived as closed-minded.

Being open to experience is associated with creativity, curiosity, and a hunger for knowledge and learning.

While to a large extent, openness is a matter of preference, it is worth understanding that those who are very closed are likely to be more rigid, less able to cope with change, and less open to persuasion.

While a high level of openness is not necessarily an advantage in marriage, it is worth understanding that extreme closedness is generally a problem in marriage, where compromise, adaptability, and willingness to try new things are a significant advantage. While openness has several facets, the aspect that most impacts marriage is the degree to which a person is capable of considering and adjusting to a different opinion. It is impossible to discuss every situation and opinion before marriage; it has therefore to be assumed that many new situations and ideas will emerge during the long-term relationship. The ability to negotiate around those situations and to discuss those issues will be much enhanced if the person you are dealing with is reasonable and willing to consider your point of view.

Extroversion

Extroversion is a personality trait typically characterized by outgoingness, high energy, and/or talkativeness. This is the least important trait. In general, the term refers to a state of being where someone “recharges,” or draws energy, from being with other people; the opposite—drawing energy from being alone—is known as introversion.

Extroverts are more bubbly, sociable, and likely to want to be around more people than introverts. People who identify as extroverts tend to search for novel experiences and social connections that allow them to interact with other people as much as possible. Someone who is highly extroverted will likely feel bored or even anxious when they’re made to spend too much time alone. By contrast, introverts may find an extrovert’s energy and enthusiasm overwhelming or difficult to tolerate.

Introverts are often wrongly overlooked, as they make less of a splash, but they typically possess an inner strength.

The important thing to recognize is that being highly extroverted can pose serious relationship challenges. Being moderately introverted can be a massive plus in a relationship – as the introvert is likely to be comfortable giving all their time and attention to just one person. To a large extent, this is personality trait depends on personal preference. It is worth being aware that many people can find people high on extroversion to be exhausting and overwhelming. If you are that way inclined, it is highly inadvisable to go for someone very high in extroversion, given the difficulties such a person will pose in a marriage to someone like you.

Winning formula

If you want to maximize both your chances of finding a marriage partner and also your chances of living happily ever after, this may be a good formula:

• Neuroticism: Low   (Emotional Stability: Moderate to high)
• Agreeableness: Very high 
• Conscientiousness: High 
• Openness: Moderate
• Extroversion: Moderate