The Grimké sisters' argument is for equal rights on the moral nature of the man.
<u>Explanation:</u>
The grimke sisters were a known name when it came about fighting for the rights of women and getting them a equal status in the society. The grimke sisters were known to be very passionate about this work and both the sisters based their arguments for equal rights on the moral nature of man and during that time, it was acceptable and it was seen totally okay for the men to have a slave, treat him badly or even to the extent of beating him.
