First of all I do not have to explain myself.
Nobody comes into life as a subjectivist or an objectivist. In order to become one of the both or no one of the both subjectivity and objectivity must be learned. This process begins in the womb.
What do the words “subject” and “object” mean originally? From here you have to begin with your research. The next thing is the development of the human object of your research. Then ask yourself: “How does a human being come into life and learn, especially learn the difference between subject and object?” Look at the test with the mirror. As a very little child one learns to recognize oneself in a mirror.
So if we want to continue our converastion here, then we have to define the words “subject” and “object”, because it is possible that you have other definitions than I have.
In order to know what a “subject” is, one must at least have a self-concept; and in order to know what an “object” is, one must be capable of distinguishing between the own self and the rest (which is outside of the own self).
Tactility already exists when the human embryo is 2 months old, taste already exists when the human fetus is 3 months old, smell already exists when the human fetus is 5 months old, hearing already exists when the human fetus is 6 months old, seeing already exists when the human fetus is 9 months old.
The sense of balance needs more time and starts when the human embryo is 2 months old.
But do you think that the embryo or the fetus is capable of distinguishing between the own self and the rest (which is outside of the own self)?