是不是所有概念都具有相同的重要性？是不是有某些概念更重要？

有一些概念在人類社會的地位會令人感到傻眼貓咪，假設我們把所外表是白色的物品視為一個類別，「白色的東西」，這就是一個很無謂的概念。有一個笑話是這樣的：
問：驢子和冰箱有什麼共同之處？
答：他們兩個都不是大象。

一但你知道驢子和冰箱是兩個概念之後，他們自然就不會是另外一個概念。

比方說，我們叫隔壁鄰居家的狗來福是「狗」，不會叫牠「動物」或「雪納瑞」。Rosch and Mervis (1975); Rosch,Mervis,Gray,Johnson and Boyes-Braem (1976) 說明基礎層的概念(basic-level concepts)是存在的。基礎層的概念會使通報性(informativeness)和區辨性(distinctiveness)達到最佳化(Murphy & Lassaline, 1997)  。通報性是當我們知道某個事物隸屬於某個概念之後，我們同時也會知道其所隱藏、未見的特質；區辨性則是能夠我們使其和非這一個概念的事物區隔。我們知道某個東西是落在「狗」這個概念時，我們知道牠會吠、會吃、是寵物，還知道牠的上屬概念就是動物(通報性)。我們也可以將這個東西和其它同樣屬於基礎層概念的「馬」、「貓」中區隔出來。

References

Atran, S. (1998). Folk biology and the anthropology of science: Cognitive universals and cultural particulars. Behavioral and brain sciences, 21(4), 547-569.

Bloom, P. (1996). Intention, history, and artifact concepts. Cognition, 60(1), 1-29.

Bloom, P. (1998). Theories of artifact categorization. Cognition, 66(1), 87-93.

Dennett, D. C. (1990). The interpretation of texts, people and other artifacts. Philosophy and phenomenological research, 50, 177-194.

Gelman, S. A. & Markman, E. M. (1986). Categories and induction in young children. Cognition, 23(3), 183-209.

Gelman, S. A. & Markman, E. M. (1987). Young children's inductions from natural kinds: The role of categories and appearances. Child development, , 1532-1541.

Gentner, D. (1978). What looks like a jiggy but acts like a zimbo? A study of early word meaning using artificial objects. Papers and Reports on Child Language Development, 15, 1-6.

Keil, F. C. (1992). Concepts, kinds, and cognitive development. mit Press.

Landau, B., Smith, L. & Jones, S. (1998). Object shape, object function, and object name. Journal of memory and language, 38(1), 1-27.

Locke, J. (1964). An essay concerning human understanding (Vol. 1690). London.

Malt, B. C. & Johnson, E. C. (1998). Artifact category membership and the intentional-historical theory. Cognition, 66(1), 79-85.

Murphy, G. L. & Lassaline, M. E. (1997). Hierarchical structure in concepts and the basic level of categorization. In (), Knowledge, concepts, and categories. MIT Press.

Murphy, G. L. & Medin, D. L. (1985). The role of theories in conceptual coherence.. Psychological review, 92(3), 289.

Nelson, D. G. K. & Students, S. C. (1995). Principle-based inferences in young children's categorization: Revisiting the impact of function on the naming of artifacts. Cognitive development, 10(3), 347-380.

Putnam, H. (1975). The meaning of" meaning". University of Minnesota Press, Minneapolis.

Rosch, E. & Mervis, C. B. (1975). Family resemblances: Studies in the internal structure of categories. Cognitive psychology, 7(4), 573-605.

Rosch, E., Mervis, C. B., Gray, W. D., Johnson, D. M. & Boyes-Braem, P. (1976). Basic objects in natural categories. Cognitive psychology, 8(3), 382-439.

Wisniewski, E. J. & Medin, D. L. (1994). On the interaction of theory and data in concept learning. Cognitive Science, 18(2), 221-281.