However , the wider significance for planetary dynamics of this purely kinematical law was not realized until the 1660s .
Although he gives the date of this epiphany ( March 8 , 1618 ) , he does not give any details about how he arrived at this conclusion .
The wider significance for planetary dynamics of this purely kinematical law was not realized until the 1660s .
Although he gives the date of this epiphany ( March 8 , 1618 ) , he does not give any details about how he arrived at this conclusion .