Summary: The Crisis of European Sciences and Transcendental Phenomenology (page 7)

It is Descartes who stands as the original founder—both of the modern idea of objectivist rationalism and of the transcendental motif that ultimately shatters it.

Descartes is the original founding genius of the whole of modern philosophy ¹.

If Galileo established the new science of nature, Descartes conceived the new idea of universal philosophy—a philosophy as universal mathematics (mathesis universalis).

Descartes seeks to provide the new rationalism with a radical foundation; yet this very foundation proves best fitted to undermine rationalism, by historically laying bare its concealed absurdity.

This is the foundation Descartes reaches through his retreat to the ego cogito, following the experience of doubt. This is the full meaning of the Cartesian epoché.

This Cartesian epoché is unprecedented in its radicalism, for it explicitly suspends the validity of all the sciences, including mathematics, and of the pre-scientific lifeworld alike.

For the first time, the very foundation of knowledge in all the sciences is put into question: sensible experience.

Certainly, ancient scepticism, initiated by Protagoras and Gorgias, maintained that the world is rationally unknowable and that human knowledge cannot transcend subjective-relative appearances.

However, this form of scepticism lacks what Descartes undergoes—his descent into the inferno ²—which allows a quasi-sceptical epochè to break through to the celestial threshold of an absolutely rational philosophy.

What Descartes discovers in radical doubt is that I, the one who performs the epoché, am not included within the objective horizon of this epoché—I find myself necessarily excluded from it in principle ³. I exist necessarily as the one who performs it. This excludes all possible doubt.

Thus, we obtain a sphere of being that is absolutely certain: that of the ego, the self. I am the one thing that is absolutely beyond doubt.

However, Descartes then misinterprets the nature of the ego he has just discovered: he psychologises it. He discovers the ego but immediately asks what it is. Is this ego identical to man—the being given in everyday life, in sensory intuition?

Descartes eliminates the body from consideration: the ego is the soul or the intellect. Yet, the problem is that the division between soul and body does not arise within the epochè but belongs instead to the theoretical framework of psychologists. The notion of the soul has no meaning within the epochè.

Descartes's fundamental error is thus the substitution of the psychological self for the ego.

Descartes inaugurates a completely new way of philosophising, one that seeks its ultimate foundation in subjectivity. And yet, he remains bound to pure objectivism, despite its subjective grounding.

For Husserl, the ego is not simply the psychological I, for the ego cannot itself appear within the world, since everything belonging to the world derives its very meaning from its operations—including the I in its ordinary, psychological sense.

The cogitations of the ego constitute, through their operations, the entire sense of being that the world can ever possess. All distinctions—I/you, inner/outer—are constituted within the absolute ego.

Descartes, in his haste to establish objectivism and the exact sciences of nature, did not systematically examine what the pure ego possesses in its own right, in terms of acts and faculties.

The early Meditations were thus, in part, a work of psychology. Descartes did not examine intentionality, which forms the essence of egological life.

Descartes marks the starting point for two major philosophical trajectories:

Rationalism, with Malebranche, Spinoza, Leibniz, Wolff, and Kant

Empiricism, with Hobbes, Locke, Berkeley, and Hume

Rationalism asserts that a universally grounded knowledge of the world in itself is possible through the geometrical method. Empiricism denies this.

Locke develops a psychology based on a naturalistic theory of knowledge.

His aim is to ground the validity of the objective sciences. To this end, Locke identifies the Cartesian ego with the soul, which knows its inner states through self-experience.

¹ II, 16, p.85
² II,17, p.89
³ ibid.