The question of extraterrestrial civilizations seems to me entirely open. Personally， I think it far more difficult to understand a universe in which we are the only technological civilization， or one of a very few， than to conceive of a cosmos brining over with intelligent life. Many aspects of the problem are， fortunately， amenable to experimental verification. We can search for planets of other stars， seek simple forms of life on such nearby planets as Mars， and perform more extensive laboratory studies on the chemistry of the origin of life. We can investigate more deeply the evolution of organisms and societies. The problem cries out for a long-term， open-minded， systematic search， with nature as the only arbitor of what is or is not likely

    Phrases & Expressions

    if any possibly none

    seek out find （sb. or sth.） by looking hard

    might very well be （very） likely to

    to date until today； yet

    band in hand with together with

    be dedicated to be devoted to； be intended to be used for

    along with together with

    depend on following directly or logically from； turn on

    so as to in order to

    in a position to able to

    brim over with have an abundance of

    cry out for need badly

    Proper Names

    Carl Sagan卡尔。萨根

    Greenbank格林班克

    West Virginia西弗吉尼亚州

    Frank Drake弗兰克。德雷克

    Cornell University康乃尔大学

    the Land of Oz奥兹国

    the Soviet Union苏联

    the Amazon亚马逊河