其实在笛卡尔的本体论中，世界上只有三种实体：心灵、物质和上帝。
In fact, in Cartesian ontology there are only three kinds of substance: mind, matter and God.
建立一个能够囊括世界上知识的本体论可能是一个巨大的任务，需要的努力可与编纂一部大百科全书比肩，并需要专家来构建，但它是切实可行的。
Building an ontology encapsulating the world's knowledge may be an immense task, requiring an effort comparable to compiling a large encyclopedia and the expertise to build it, but it is feasible.
本体借用哲学词汇，是归属于描述世界上实体类别及其它们之间如何联系的科学。
Ontology is a term borrowed from philosophy that refers to the science of describing the kinds of entities in the world and how they are related.
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