The reason why so less women were involved in the founding of psychology were because initially women experiences and founding were not documented. They were not taken seriously. Their experiences were not considered pivotal to the role of psychology.
Explanation:
Phycology is the study and behaviors of human brain. The mind is complex structure and one has to be very careful while handling it.
Women previously were not considered smart enough to be able to participate in any scientific research. Women had to use a fake name or a mans name in order to get their work the recognition and some attention from its fellow scientists.
Women were always put on the sidelines whenever it came to engaging in public spheres. If we go back to earlier centuries, we'll find that women were considered academicallyweak and no one took them seriously, instead if they showed interest in mere learning they were labelled as hyterical and put into mental asylums.
So to consider the question why so few women were engaged in the founding of psychology, it becomes pretty clear. Psychology is mainly considered with Freud and Jung. So the thought of women engaging in it was absurd as at that point of time as women were barred from these segments.
They had very little power or none at all, even if they dared to engage themselves in these men dominating sectors, they were immediately made fun of and it resulted in severeconsequences such as debarred from their own society. A few among them such as Virginia Woolf or Alice Walker were able to make their way inside this male wooven tapestry and made themselves heard.