The single condition wash that they should never meet.
Explanation:
Tchaikovsky thought that he would not live up to Nadezhda Von Mecks expectations, and he also found their relationship awkward. The two of them did not know whether they liked each other or not, and the fact that money was brought up in almost all the letters made Tchaikovsky feel uncomfortable,
They did meet a couple of times, but the meetings were by chance. The first meeting was in a park, were Tchaikovsky was taking a stroll, and Madame Von Meck was on her way home, and the second meeting was in an Opera house.
Sociological affinity refers to "spiritual parentage", curiosity, as well as other behavioral common interests. This is distinguished by elevated degrees of friendship through collaboration, also recognized as affinity collectives or groups, typically in similar organizations.
Individuals who believe they connect collectively, both with as well as without legitimate as well as blood relations, and also who identify oneself as kin.
So that the above would be the appropriate answer.