This study aims to discover the theme of popular physics book, The Grand Design, through corpus linguistics and discourse analysis as well as how the authors of the book describe the field of study which in fact is not their main focus to work on. In this case, the authors are physicists and cosmologists who attempt to use quantum to interpret the history if the universe. There were two terms, quantum and cosmology, which would be examined to gain the number of appearance in the book. A computer-based corpus software, AntConc v 3.4.3w and chi square test were employed to gain the hit numbers and the significant value of the possible different number appeared. This result would answer the question of what the theme of the book is. The procedure of corpus analysis, which raw text is directly analyzed, was used along with collocation and concordance analysis. After the data was gained from collocation and concordance analysis, discourse analysis was applied to obtain the profound findings of how the authors assert their opinion of quantum in the study of the cosmology. This paper resulted that quantum has more hit numbers than cosmology. In addition, it was found that the theory proposed in this book was quite inadequate in a certain circumstance.