资料题：We can infer from the passage that（  ）。

Choosing a travel companion is at least as uncertain as choosing marriage partner.The chances of success are perhaps even less.The initial stages of both journeys are filed with enthusiasms, indulgences, and a fairly consistent closing of the eyes to that which may later become,if not unacceptable, at the very least unpalatable(味道差不好吃).No law of casualty exists to insist that in choosing a travel companion you will lose a friend.But it's not unlikely.The odds depend om the length and the rigorousness of the tip.Some friendships have strength that will.withstand even travel; others, based on happen-stance(意外事件), are by nature short-lived and travel merely hastens their dissolution.Perhaps I should make it clear that in discussing this matter of travel companions I am confining myself to Platonio friendships.Intimate friends may well be the best companions of all, but entirely different rules of travel prevail.Compromises and concessions, demands and entreaties to and from such companions clearly stem from a recognized emotional base that colors every issue.I'll confine myself, then, to companions, male and female, who are sharing a trip solely for company.Why bother at all with a travel companion? Why not travel alone, in single blessedness,unencumbered and 8wifly pursuing one's goal? Some of the answers are obvious: a congenial fellow traveler eases the stress and tensions, adds to the delights and rewards and pays half the bills.If the threat of loneliness is frightening, even a grumpy(脾气坏)companion will foretell that, and quite often bring you to the point where you devoutly wish you were alone.Finding that suitable companion is something of an ant and something of a gamble.But thechoice should be determined by one cardinal rule: both travelers should be going on the trip withthe same idea in mind.They should hold in common a theory of travel.