we can stretch our personalities, but only up to a point. Our inborn temperaments influence us, regardless of the lives we lead. A sizable part of who we are is ordained by our genes, by our brains, by our nervous systems. And yet the elasticity that Schwartz found in some of the high-reactive teens also suggests the converse: we have free will and can use it to shape our personalities.
These seem like contradictory principles, but they are not. Free will can take us far, suggests Dr. Schwartz’s research, but it cannot carry us infinitely beyond our genetic limits. Bill Gates is never going to be Bill Clinton, no matter how he polishes his social skills, and Bill Clinton can never be Bill Gates, no matter how much time he spends alone with a computer.
We might call this the “rubber band theory” of personality. We are like rubber bands at rest. We are elastic and can stretch ourselves, but only so much.

Yet the evidence, from twin studies, from the children of immigrants and from adoption studies, is now staring us in the face: people get their personalities from their genes and from their peers, not from their parents.

Not everyone is allotted the chance to become a personality; most remain types, and never experience the rigor of becoming an individual. But those who do so inevitably discover that these struggles bring them into conflict with the normal life of average people and the traditional values and bourgeois conventions that they uphold. A personality is the product of a clash between two opposing forces: the urge to create a life of one's own and the insistence by the world around us that we conform. Nobody can develop a personality unless he undergoes revolutionary experiences. The extent of those experiences differs, of course, from person to person, as does the capacity to lead a life that is truly personal and unique.

According to Free Trait Theory, we are born and culturally endowed with certain personality traits — introversion, for example — but we can and do act out of character in the service of “core personal projects.

In fine, human character is moulded by a thousand subtle influences; by example and precept; by life and literature; by friends and neighbours; by the world we live in as well as by the spirits of our forefathers, whose legacy of good words and deeds we inherit. But great, unquestionably, though these influences are acknowledged to be, it is nevertheless equally clear that men must necassarily be the active agents of their own well-being and well-doing; and that, however much the wise and the good may owe to others, they themselves in the very nature of things be their own best helpers (p.31).

For what are our faculties, but the extension of our personality? and what is property, but an extension of our faculties?

The personality is seldom, in the beginning, what it will be later on. For this reason the possibility of enlarging it exists, at least during the first half of life. The enlargement may be effected through an accretion from without, by new vital contents finding their way into the personality from outside and being assimilated. In this way a considerable increase of personality may be experienced. We therefore tend to assume that this increase comes only from without, thus justifying the prejudice that one becomes a personality by stuffing into oneself as much as possible from outside. But the more assiduously we follow this recipe, and the more stubbornly we believe that all increase has to come from without, the greater becomes our inner poverty. Therefore, if some great idea takes hold of us from outside, we must understand that it takes hold of us only because something in us responds to it and goes out to meet it. Richness of mind consists in mental receptivity, not in the accumulation of possessions. What comes to us from outside, and, for that matter, everything that rises up from within, can only be made our own if we are capable of an inner amplitude equal to that of the incoming content. Real increase of personality means consciousness of an enlargement that flows from inner sources. Without psychic depth we can never be adequately related to the magnitude of our object. It has therefore been said quite truly that a man grows with the greatness of his task. But he must have within himself the capacity to grow; otherwise even the most difficult task is of no benefit to him. More likely he will be shattered by it…

It is not only the violin that shapes the violinist, we are all shaped by the tools we train ourselves to use, and in this respect programming languages have a devious influence: they shape our thinking habits.

Everybody has a second personality, it may possess and make you do whatever it likes.

How does the personality come into being? By memory. By identifying the present with the past and projecting it into the future. Think of yourself as momentary, without past and future, and your personality dissolves.

primary mental abilities and perceptual and motor skills are the most influenced by heredity, while personality traits are the least influenced.

There is such pressure in the West to be likable that people often reconfigure their entire personality depending on the person they’re dealing with.

Psychologists often discuss the difference between “temperament” and “personality.” Temperament refers to inborn, biologically based behavioral and emotional patterns that are observable in infancy and early childhood; personality is the complex brew that emerges after cultural influence and personal experience are thrown into the mix. Some say that temperament is the foundation, and personality is the building.

Each of us has his or her own distinct personality. But overlaid on top of that are tendencies and assumptions and reflexes handed down to us by the history of the community we grew up in, and those differences are extraordinarily specific.