文章通過探索"本質"概念的產生在人認識本能上的起源,將人們對"本質"的認識歸結為一種語言現象,繼而考察"本質"一詞作為思維方式和研究共同體認識范式的意義,認為"本質"在作為范式時,在現代已經很少作為"真理"的面目出現,而"本質"作為思維方式,只是至今還是現代科學主流方法特征的還原論的特例。但是,作為哲學概念,"本質"并不能用于科學研究。因而從一般系統論的角度出發,推導出系統目的類似于事物的"本質",從而使事物"本質"獲得了一個在科學研究中近似的替代品。繼而考察了圖書館學研究對象的研究方法,指出迄今只有"抽象圖書館學""知識集合論""可獲得性論"的研究使用了現代一般科學方法論,并因此獲得了研究相應觀點內部聯系的基本思路,形成了一定的理論解釋力。理論解釋力是理論說服力的來源。理論推演是產生大量新問題的主要方法,但同時也會限制研究者的思路。這是一個"硬幣的兩面",無法避免。圖書館學的現象領域作為社會現象的一部分,可以具有多種"本質",但這無關緊要,重要的是圖書館學理論研究要形成研究思路和理論話語。

This paper discusses the concept of essence from the origins of human cognition. People’s understanding of essence can be concluded as a linguistic phenomenon. Then the essence is investigated either as amode of thinking or the cognition paradigm of a research community. In the latter case,the essence rarely appearsas the truth in research paradigms today. On the other hand,as a mode of thinking,the essence is only a specialcase of reductionism. Therefore,the essence,as a philosophical concept,cannot be readily applied in modernscientific research. However, from the viewpoint of general system theory, the essence of a system may be interpreted as the purpose(s) of that system. In this way,the essence finds an approximate place to substitute inscientific research. This paper continues by examining the research methods of library science research objects andpoints out that only"abstract library science","knowledge set theory"and"accessibility theory"have beenengaging the methodology of scientific research. In other words,the internal connection of relating viewpoints isexplored to offer an explanation;and explanatory power is the basis of persuasion for scientific theories. Theoreticaldeduction is the main tool to suggest new questions and new perspectives. However, it will also restrict aresearcher’s way of thinking. They are two sides of the same coin and cannot be avoided. To conclude,the researchobjects of library science,being parts of social phenomenon,can have many essences. This is not important. Themore important thing is to give library science a theoretical framework for discourse.