The skeptic philosophers of the eighteenth century, especially the Britons George Berkley and David Hume, go even further in demonstrating the absolute necessity of understanding the mind to validate scientific undertakings. Descartes had initiated this meditation; but he forestalled the power of his questions by invoking the existence of God to validate the relevance of the data gathered through the senses. Using God as proof became invalid in a world that presumes that the mind, even if it has particular properties, is part of the dynamics of nature. If we are not able to validate the pertinence of sensory data, then every construction based on these data could be simply a delusion. The same reasoning can be applied to the logical systems produced by the human mind. Thus, science must be validated not only by the technology whose construction it promotes but also by demonstrating that the mind is capable, at least sometimes, of observing and thinking in an adequate and appropriate manner. We know that false reasoning can lead to useful technologies. Berkley and Hume radicalized this critique by exposing it in a more systematic way:
Thus world-enigmas now enter the stage, of a sort previously never imagined, and they bring about a completely new manner of philosophizing, the epistemologicalâ philosophy, that of the theory of reason.â Soon they also give rise to systematic philosophies with completely novel goals and methods. (Husserl, 1936, 11.13, p. 68)
It is necessary to understand how thinking works to understand what the mind can do and the value of its products. If Descartes’s I think, therefore I amâ shows the necessity of having a psychology, Kant’s Critique of Pure Reason demonstrates that it is possible to begin to propose realistic and pertinent models concerning the functioning of the mind and its creativity.