"Go with the flow." "Go for it." "Take the plunge." "Just do it."
What these phrases have in common is they tell us that restraints or inhibitions are something negative. The perfect person who is interesting, alive, happy and kicking, is a person who is free of those. This is what the world teaches us today, from babyhood and on.
After thousands of years of clear social boundaries (even the nations back in the day, "gidru es atzmam"), where did this weird worldview come from, that the greatest value is breaking boundaries and being free of restraints?
AN UPSIDE DOWN WORLD
It isn't pleasant to admit this but I attribute the onset of the removal of boundaries to the birth of psychology. Psychology developed at the end of nineteenth century, and one of its first precepts was that suppression, lack of awareness of what you're really feeling, about what is going on in your psyche is bad, while awareness and the ability to allow emotions to surface to where they are accessible to us, is something good. This way of thinking said that awareness itself is enough to free one or do away with various symptoms which are the psyche's roundabout way of connecting us to what's happening inside it.
That's all fine and good. We can stand behind that. But there were people who took this a step further and from the world of the psyche they applied it all to the world of action. We don't need to suppress our subconscious urges or desire or feelings, right? Then if we don't suppress them in our inner world, we won't suppress them in our behavioral world. These people confused awareness (which actually enables us to better control ourselves, enables more "mind rules the heart," because those things outside of our awareness are difficult to impossible to impose control over and they come out in indirect, uncontrollable ways), and the absence of actual boundaries (for not everything that arises in our inner world is meant to be turned into action; on the contrary, the beinoni remains a beinoni despite the thoughts that arise from his heart to his mind, as the Tanya says).
And so we've come to being in a world which constantly teaches us that "the heart rules the mind from birth," and a person who lives with clear boundaries and reins in his urges, is a rigid, inflexible, uninteresting, pathetic person.
THOSE WHO DELAY GRATIFICATION ARE MORE SUCCESSFUL
Let's take a closer look at the subject of restraint, inhibition or the ability to delay gratification.
In 1970, Walter Mischel, a professor of psychology at Stanford University, conducted an experiment which became very famous, called the Marshmallow Experiment. A marshmallow was placed in front of little children (3.5-6 years old) and someone explained to them that they can eat the marshmallow now, but if they wait a while, they'll get two marshmallows. In long-term studies following the lives of these same children, it has been clearly demonstrated that the children who waited not only got more to eat but were more successful in life - academically, professionally, health-wise, etc.
UNDERSTANDING 'ISKAFYA'
It's fairly obvious that this discussion leads us to a fundamental concept in Chassidus - iskafya. In chapter 12 of Tanya, it says, "every person may, with the power of the will in his brain, restrain himself and control the drive of his heart's lust, preventing his heart's desires from finding expression in deed, word, and thought."
The Alter Rebbe is telling us an amazing thing. The raw material of the ability for self-control, to delay gratification, is within every one of us from birth. Each of us was born with the potential for restraint and if we don't actualize it, it's only because we weren't taught enough, we weren't trained enough, and we don't train ourselves here and now.
SO, HOW DO WE DO IT?
As a practical example of iskafya, the Alter Rebbe mentions (in chapter 27) the Torah scholars who delayed their meal by two hours, just to train their iskafya "muscle," and to teach themselves to delay gratification. In our generation, which is weak, so that the Rebbe said that fasting is not for us, perhaps we shouldn't train ourselves with food, but we definitely should train ourselves. We and our children need to train ourselves to delay gratification (which is harder for us in these generations). We can do this by delaying screen time (relevant to all ages), delaying treats until after doing household chores, delaying conveying criticism for later (if it's between the couple, it can be delayed until the children are asleep, and one can hope that once delayed, it will remain delayed), delaying playing with friends until after homework is done, etc.
Bottom line, delaying gratification brings joy to life. Things that are quickly obtainable feel like "bread of shame," and their value is diminished. The more we wait for something, and for sure if we worked for it, the more its value rises and its pleasure factor increases. Not surprisingly, today's generation of abundance and instant everything is sadder than ever and more anxious than ever.
Restraint, the mind controlling the heart, simply improve one's quality of life.