Modern thought, in philosophy and science, has challenged traditional theism. In philosophy, Descartes’ turn away from Aristotelian metaphysics opened the door for Hume’s skeptic empiricism. And while Leibniz attempted to construct a metaphysics of perfection, ultimately Kant’s critique of reason reduced God to a “regulative concept,” and Spinoza’s philosophy challenged German idealism and became incorporated into it. As Clayton explains, the development of modern philosophy and theology-centered skepticism—especially in regard to metaphysical issues. “God language” collapsed with the scholastic tradition, and metaphysics has been written off as “meaningless,” “untestable,” “vacuous,” “unfalsifiable,” and therefore unscientific. Through all this, what emerged was a need for new ways to conceptualize God’s relationship with the world. Muhammad Iqbal also took issue with classical theism. Particularly, Iqbal took issue with any conception of God that was, as he understood it, too Platonic, too stationary. He credited Platonism with the decay of Islamic civilization and culture. Greek thought in general was “too abstract, too speculative, not inducing man to fruitful work.” Additionally, the concept of God and His relationship to the world derived from the Aristotelian tradition (which had a strong influence on many of the Islamic tradition’s most prolific philosophers) did not line up with God as described in Islamic sources—particularly the Quran. As Schimmel explains, “the Aristotelian concept of eternity of the world was exactly opposed to the Islamic belief in creatio ex nihilo, as opposed as the static prima causa or the immovable mover of philosophy was to the dynamic and ever-active God of the Quran, who is creating a world in flux.” Iqbal’s aversion to the classical tradition is further validated by the challenges posed against classical theism in modern thought.