Language styles used by academics working in disciplines are different, possibly reflecting how different types of knowledge are conceived, communicated and taught. Most of the studies on the communication style of academics are based on analyses of pre-prepared academic writings and formal speeches. It is not known whether such differences in language styles are also practised in informal, colloquial communications. In this paper, we report a Linguistic Inquiry and Word Count (LIWC) analysis of the telephone interviews given by 82 Nobel Prize laureates in the fields of natural sciences (chemistry, physics, physiology, or medicine) and economic sciences. LIWC analysis identifies differences in usage frequency of words in various language categories. The result shows a higher use of money- and power-related words by economic laureates and a higher use of second-person pronouns among science laureates. When second-person pronouns were used, economic laureates tended to use them as a general reference, while scientists tended to use them as courtesy sentences or discourse markers. These observations indicate that different language styles are used by scholars of different research fields even in their impromptu verbal communications. It is possible that word choices by economists are influenced by the content of economic studies, which are concerned with influencing the external environment and by their preference in describing processes and actions. A more involved and high level of cautions, alertness, and precision in conversion may be indicated in the speaking style of natural scientists.