Scientific ideas can be difficult to affirm if they contradictearlier-developed intuitive theories. Here, we investigatedhow instruction on counterintuitive scientific ideas affects theaccessibility of those ideas under time pressure. Participants(138 college undergraduates) verified, as quickly as possible,statements about life and matter before and after a tutorial onthe scientific properties of life or matter. Half the statementswere consistent with intuitive theories of the domain (e.g.,“zebras reproduce”) and half were inconsistent (e.g.,“mushrooms reproduce”). Participants verified the latter lessaccurately and more slowly than the former, both beforeinstruction and after. Instruction did, however, increaseaccuracy for counterintuitive statements within the domain ofinstruction, but changes in accuracy were not accompanied bychanges in speed. These results confirm the conclusion drawnfrom studies with professional scientists that scientific ideascan be prioritized over intuitive ones but the conflict betweenscience and intuition cannot be eliminated altogether.