Is it permissible to think about future matters related to marriage with a girl one intends to propose to?

Thinking about the girl one intends to marry is permissible, as long as it does not involve dwelling on her merits or excessive contemplation. Thinking about matters after marriage, as a form of planning for the future, is not blameworthy, provided that one avoids trivial thoughts. However, thinking about going out with her before marriage is not advisable, as it may lead to disobedience.