That kinda depends on which kind of cell. There are primitive, open-ended, unactivated cells (ala stem cells); and then there are individuated, activated, specialized cells (like brain cells).
An adult human being is made up of a whole lot of different kinds of specialized cells. Some of these specialized cells make up one's brain, which thinks and feels and remembers and reasons.
But early on in the human life cycle, everyone starts out as a single-cell organism, in the form of a fertilized egg or zygote. This cell is open-ended, in that various parts of its DNA can become activated to cause the cell to become anything within a human body.
But it does not actually do so. Instead, the zygote divides and multiples, producing near-exact copies of itself. And this continues, with the cells multiplying so many times that they form a tiny little soccer-ball-looking mass. At this point, the cells are all still copies of one another, with no specialization and no individuation.
Eventually, the ball of cells grows sufficiently that a hollow pocket forms inside the ball. It is at this point that the cells begin to demonstrate some differentiation from one another. The cells on the inside of the hollow ball begin to perform certain functions that differ from the cells on the outside of the ball. This lining of differentiated interior cell goes on to become the inner organs of the gestating human being, and the outer lining of cells goes on to become the muscles, skeleton, and skin.
The question as to when a self/psyche/mind or soul develops within a human being has not been definitively answered. Some religions claim that an external spirit is attached at the moment of conception in the womb. But there is no evidence of mind within a zygote, or even at the blastocyst (hollow ball of cells) stage of the human life cycle.
I suppose that one could study psychology and try to pinpoint an exact moment when a self/psyche/mind presents itself.
But it seems to me that a mind doesn't just pop into existence, all at once. It is a gradually unfolding, developing thing. Just as the cells within an in-utero human being take on new, specific roles and functions that differentiate them from one another; a young human being slowly and gradually begins to respond to its surroundings in a way that demonstrates that it is becoming aware of those surroundings, and ultimately aware of itself too.
To my knowledge, no one human cell is capable of this. Human thought and emotion require an interplay of numerous different types of specialized cells. Self-awareness happens when there are a sufficient number of specialized brain cells to make it happen, and there are a sufficient number of other types of body tissue cells to support it, and there are a sufficient number of external experiences for the young human being to learn to differentiate itself from its surroundings.
It's not so much "when did a human being become self-aware?" (single precise moment in time), so much as "when was a human being becoming self-aware?" (a more extended time interval).
reply
share