The article elaborates and tests the hypothesis that there are different types of aca demic knowledge that exert different effects on economic growth. Knowledge items differ with respect to the specificities of both their generation and exploitation pro cesses. Building upon these bases, the article articulates the crucial distinction between knowledge as a capital good, necessary to produce all the other goods at lower costs and knowledge as a final good that affects directly the utility of consu mers. We use Organisation for Economic Co-operation and Development data about the disciplinary composition of the research and development expenses in higher education and total factor productivity growth in the years 1998-2008 in 13 countries to test the hypothesis. The results confirm the strong differences in the con tribution of each discipline to growth accounting.