Unnecessary association with women, even with one's mother, sister or daughter, is strictly prohibited. This is human civilization. A civilization that allows men to mix unrestrictedly with women is an animal civilization. In Kali-yuga, people are extremely liberal, but mixing with women and talking with them as equals actually constitutes an uncivilized way of life.

(From Srila Prabhupada's purport to SB 7.12.8)