Memes are an interesting fairly new phenomenon in their current state. The original definition comes from biology and is defined as “an element of a culture or system of behaviour passed from one individual to another by imitation or other non-genetic means“, however with the advent of social media, they have taken a similar form to heuristics, to communicate something which is known within a group through a humorous graphic of some kind.
In the beginning I wasn’t a huge fan of the soy meme, however I’ve grown quite fond of it in the same way I like the constructs of “Alpha“, “Beta” and many others we use within the manosphere. I looked up the definition of the term soy on urban dictionary and it was defined as:
state in which one is emotionally vulnerable, and/or is being overly sensitive. 
However, must like the definition of hypergamy in the mainstream is more or less “marrying up“, the definition is not extensive and inclusive enough. Marrying up is a consequence of hypergamy, not what it is, in the same way that being overly sensitive and/or emotionally vulnerable is a consequence of being soy, not exactly what the construct entails.
The meme to my knowledge, comes from the fact that soy products, including tofu and soy milk contain daidzein and genistein two chemicals that act so similar to estrogen that they are referred to as phytoestrogens. In a man, these can have the same effect as taking estrogen, even at a low-level of consumption. Some of the symptoms of high estrogen in men include:
High estrogen levels in men contribute to prostate cancer and heart disease as well as gynecomastia ( enlarged breasts).As the testosterone is transformed into estrogen the low levels of testosterone can cause many unpleasant symptoms including loss of muscle mass, fatigue, low libido, erectile dysfunction. Furthermore, excessive estrogen in men raises body fat and can contribute to diabetes and high lipids. 
While physical weakness is often a core characteristic in men that are deemed to be “soy” in the manosphere, a much more common implication refers to their psychology, mindset, frame and inner world functioning more like that of women, and thus their actions and behaviors are more like those of women than of men.
I think it’s best to start with the psychology of “soy” from the perspective using the big 5/OCEAN personality metric. I used this in a couple of earlier essays, because it is a useful metric to compare and contrast personality from the perspective of intersexual dynamics. For instance, men are generally more dominant and disagreeable, while women are more neurotic and agreeable. Thus, in men, we can see that Dark Triad traits have a positive correlation with mating, in that men who are narcissistic, Machiavellian and psychopathic have on average more sexual partners than men who are
To give a quick rundown on the gender differences on the Five Factor test :
Agreeableness: This trait consists of among others, tendency towards cooperation, maintaining social harmony and considering the concerns of others. Tender-mindedness, altruism, empathy and kindness are also part of this factor. Women consistently score higher than men on agreeableness, meaning that men are on average more disagreeable than women. Meaning, more competitive, less concerned with maintaining social harmony, and more inclined towards being exploitative of others.
Neuroticism: This refers to the tendency to experience negative emotion and related processes in response to punishment and threats. The only facet of neuroticism where women do not consistently score higher than men is anger, while they consistently score higher than men on anxiety, depression, self-consciousness and emotional lability.
Conscientiousness: This refers to traits related to self-discipline, organization, and impulse control. Women score somewhat higher than men on some facets of conscientiousness, such as orderliness, dutifulness and self-discipline, but no consistent gender difference has been found.
Extraversion: This trait reflects sociability, assertiveness, and positive emotionality. For this trait, few gender differences have been found on the top level, however, on the underlying factors for the trait, women tend to score higher for gregariousness, warmth and positive emotions. Men score higher than women on assertiveness and excitement seeking.
Openness/Intellect: The trait reflects imagination, creativity, intellectual curiosity, and appreciation of esthetic experiences. On the factor level, there are few sex differences here, however on the facet level, women tend to score higher on esthetics and feelings, men tend to score higher on ideas.
In defining soy-chology, one can therefore conclude that they would demonstrate traits that are more correlated with the female scores on the Big 5, meaning that they are neurotic, agreeable, gregarious and warm, open to esthetics and feelings. How would this manifest in behavior? A man who is agreeable, submissive, emotionally open, lacks confidence, is prone to depression and anxiety, risk avoidant, a bit emotionally unstable and incapable of dominance. Based on the effects of estrogen in men, one would also expect low muscle mass, reduced libido and increased body fat.
Following The Money
A very basic premise that I’ve covered before and which is supported by data is that women rate 80% of men as below averagely attractive, where men rate women along a bell-curve. The major conclusion that came out of the essays I wrote based on Dataclysm and OkCupid data, is that men compete with each other for maximal sexual revenue, where women compete with each other to achieve maximal sexual profit. Meaning that men seek quantity and women seek out quality.
However, if one starts from the data that women rate 80% of men as below average, which if reduced to a binary scale would mean that the top 80% of women are competing for the attention of the top 20% of men, while the bottom 80% of men are competing for the affections of the bottom 20% of women. Something which is supported by the data from OKcupid.
The bottom 80% of men, if unable to compete in the traditional avenues of competence, dominance, assertiveness, frame control, and social value, how can they compete? The “Sneaky Fucker” strategy is a classic, which is when an effeminate, and non-threatening male sleeps with all his female friends.
Identifying with the feminine is another popular strategy, where a male may befriend a woman or multiple women and attempts to get laid through covert contracts. They often justify their manipulations in “The end justifies the means” in that they are engaging in extensive manipulation in order to realize an outcome beneficial to the woman.
Creating niches is another popular strategy. The sexual market place is split into many different markets and industries, where value differs slightly within each one. A woman who is an 8 by appearance in a small mid-western town may be a 5 or 6 in L.A, Vegas or Miami. A man who is a 9 within one subculture or group, may be a 6 or 7 in another subculture or group due to differing preferences. For instance, within the “Gamer” sub-culture, the top performing men are highly sought after by the women within the sub-culture despite often being of much lower sexual market value in “the wild“.
I referenced Charlie Manson in a recent essay, now Charlie was 5 ft 2 inches, weighed about 100 lbs, and does not really tick any of the “Alpha male who has a harem of 5 – 10 women fighting for his attention and doing his bidding” boxes. Yet, through his ability to draw people into his frame, he was able to create for himself a niche sexual market place where he was indeed the alpha.
This is a general strategy that has been fielded throughout history, men who are unable to compete with or usurp the leaders within a domain, create their own domain where they can become leaders. Alternatively, as Manson did they can infiltrate an existing movement, and co-opt it towards their own ends. Jim Jones is a prime example of the latter, a man who began his rise to cult-leader as a Methodist minister, and then slowly stripped away many of the religious teachings in favor of his own doctrine.
Summary and Conclusions
I like observation over asking questions for the reason that we are all trained from childhood to filter ourselves and to think before we speak. As we progress through the educational system and transition to corporate existence, this ability is often encouraged and further developed to the point where one can do a 45 minute presentation and not really say anything. This is why children, often to the abject horror of their parents often say things that are true, yet highly inappropriate in the context and why the term “In vino veritas” was invented, a man under the influence is more likely to speak those thoughts that they would not speak while sober.
When we observe children, adolescents and teenagers interact, we can see distinct behavioral patterns within them that continue throughout life, they merely become more refined with practice. Anyone who has spent time in a majority female workplace knows that it has a tendency to turn into “Mean Girls: Corporate Edition” , and anyone who has spent a lot of time in a majority male workplace (ideally 100% male), knows that it often takes on a very locker room or frat house vibe.
These are natural behavior patterns based on innate preferences for behavior, communication and environment that continue throughout life, we just become more adept at concealing them.
The reason why the soy meme caught on within the manosphere, is that it perfectly encapsulates a type of man that most of us are familiar with. A man who rejects masculinity, often on both a psychological and physical level, and instead attempts to realize the male reproductive strategy through differentiating himself as “Not like those other bastards who just want you for your body” or “I’m a nice guy who submits to your frame“.
“Soy“, which is sold as a healthy alternative to animal protein, but that appears to have many negative hormonal effects on men, perfectly encapsulates the adoption of a feminine-first mindset and rejection of the male tendency towards physicality and competition. Soy does have negative physical effects on men, and the “Soy boy” meme is simply the logical extension of “non-masculine physiology leads to a non-masculine psychology”.
In essence, the man attempts to transform himself from battering ram to Trojan horse, in the process adopting female perspectives, frames and approaches to life. Instead of being direct they are indirect, instead of being overt they are covert, instead of stating they hint, and instead of demanding they ask. In their monumental effort to not be those “mean guys“, they transform themselves into Mean Girls.