"René Descartes is often credited with being the 'Father of Modern Philosophy.' This title is justified due both to his break with the traditional Scholastic-Aristotelian philosophy prevalent at his time and to his development and promotion of the new, mechanistic sciences. His fundamental break with Scholastic philosophy was twofold. First, Descartes thought that the Scholastics’ method was prone to doubt given their reliance on sensation as the source for all knowledge. Second, he wanted to replace their final causal model of scientific explanation with the more modern, mechanistic model."
"Together with several apparently self-evident principles (such as the principle of sufficient reason, the law of contradiction, and the identity of indiscernibles), Leibniz uses his predicate-in-subject theory of truth to develop a remarkable philosophical system that provides an intricate and thorough account of reality. Ultimately, Leibniz’s universe contains only God and non-composite, immaterial, soul-like entities called 'monads.' Strictly speaking, space, time, causation, material objects, among other things, are all illusions (at least as normally conceived). However, these illusions are well-founded on and explained by the true nature of the universe at its fundamental level. For example, Leibniz argues that things seem to cause one another because God ordained a pre-established harmony among everything in the universe. Furthermore, as consequences of his metaphysics, Leibniz proposes solutions to several deep philosophical problems, such as the problem of free will, the problem of evil, and the nature of space and time. One thus finds Leibniz developing intriguing arguments for several philosophical positions—including theism, compatibilism, and idealism."
"'Hume is our Politics, Hume is our Trade, Hume is our Philosophy, Hume is our Religion.' This statement by nineteenth century philosopher James Hutchison Stirling reflects the unique position in intellectual thought held by Scottish philosopher David Hume. Part of Hume’s fame and importance owes to his boldly skeptical approach to a range of philosophical subjects. In epistemology, he questioned common notions of personal identity, and argued that there is no permanent 'self' that continues over time. He dismissed standard accounts of causality and argued that our conceptions of cause-effect relations are grounded in habits of thinking, rather than in the perception of causal forces in the external world itself. He defended the skeptical position that human reason is inherently contradictory, and it is only through naturally-instilled beliefs that we can navigate our way through common life."
"Hume shows that experience does not tell us much. Of two events, A and B, we say that A causes B when the two always occur together, that is, are constantly conjoined. Whenever we find A, we also find B, and we have a certainty that this conjunction will continue to happen. Once we realize that 'A must bring about B' is tantamount merely to 'Due to their constant conjunction, we are psychologically certain that B will follow A', then we are left with a very weak notion of necessity. This tenuous grasp on causal efficacy helps give rise to the Problem of Induction–that we are not reasonably justified in making any inductive inference about the world. Among Hume scholars it is a matter of debate how seriously Hume means us to take this conclusion and whether causation consists wholly in constant conjunction."
"Bento (in Hebrew, Baruch; in Latin, Benedictus) Spinoza is one of the most important philosophers—and certainly the most radical—of the early modern period. His thought combines a commitment to a number of Cartesian metaphysical and epistemological principles with elements from ancient Stoicism, Hobbes, and medieval Jewish rationalism into a nonetheless highly original system. His extremely naturalistic views on God, the world, the human being and knowledge serve to ground a moral philosophy centered on the control of the passions leading to virtue and happiness. They also lay the foundations for a strongly democratic political thought and a deep critique of the pretensions of Scripture and sectarian religion. Of all the philosophers of the seventeenth century, Spinoza is among the most relevant today."
"His physical science is largely Cartesian, both in content and rationalistic method. It is harshly dismissive of the 'occult qualities, intentional species, substantial forms, and a thousand other trifles' (letter 60, to Boxel) of pre-revolutionary scholastic natural philosophy. It is likewise antagonistic to the new Baconian experimentalism, holding that empirical findings can at best present examples of what reason itself demonstrates. Spinoza neither perceives the particular difficulties for Cartesian physical theory that lead Leibniz to revive both finalism and substantial forms, nor foresees the Newtonian theory of universal gravitation whose mathematical and empirical superiority to the Cartesian vortex theory lead to its universal acceptance, despite its own revival of occult powers in the form of forces operating at a distance."
"Thomas Hobbes (1588–1679), whose current reputation rests largely on his political philosophy, was a thinker with wide-ranging interests. In philosophy, he defended a range of materialist, nominalist, and empiricist views against Cartesian and Aristotelian alternatives. In physics, his work was influential on Leibniz, and led him into disputes with Boyle and the experimentalists of the early Royal Society. In history, he translated Thucydides’ History of the Peloponnesian War into English, and later wrote his own history of the Long Parliament. In mathematics he was less successful, and is best remembered for his repeated unsuccessful attempts to square the circle. But despite that, Hobbes was a serious and prominent participant in the intellectual life of his time."
"Born in 1770 in Stuttgart, Hegel spent the years 1788–1793 as a student in nearby Tübingen, studying first philosophy, and then theology, and forming friendships with fellow students, the future great romantic poet Friedrich Hölderlin (1770–1843) and Friedrich von Schelling (1775–1854), who, like Hegel, would become one of the major figures of the German philosophical scene in the first half of the nineteenth century. These friendships clearly had a major influence on Hegel’s philosophical development, and for a while the intellectual lives of the three were closely intertwined."
"John Locke (b. 1632, d. 1704) was a British philosopher, Oxford academic and medical researcher. Locke’s monumental An Essay Concerning Human Understanding (1689) is one of the first great defenses of modern empiricism and concerns itself with determining the limits of human understanding in respect to a wide spectrum of topics. It thus tells us in some detail what one can legitimately claim to know and what one cannot. Locke’s association with Anthony Ashley Cooper (later the First Earl of Shaftesbury) led him to become successively a government official charged with collecting information about trade and colonies, economic writer, opposition political activist, and finally a revolutionary whose cause ultimately triumphed in the Glorious Revolution of 1688. Among Locke’s political works he is most famous for The Second Treatise of Government in which he argues that sovereignty resides in the people and explains the nature of legitimate government in terms of natural rights and the social contract. He is also famous for calling for the separation of Church and State in his Letter Concerning Toleration. Much of Locke’s work is characterized by opposition to authoritarianism. This is apparent both on the level of the individual person and on the level of institutions such as government and church. For the individual, Locke wants each of us to use reason to search after truth rather than simply accept the opinion of authorities or be subject to superstition. He wants us to proportion assent to propositions to the evidence for them. On the level of institutions it becomes important to distinguish the legitimate from the illegitimate functions of institutions and to make the corresponding distinction for the uses of force by these institutions. Locke believes that using reason to try to grasp the truth, and determine the legitimate functions of institutions will optimize human flourishing for the individual and society both in respect to its material and spiritual welfare. This in turn, amounts to following natural law and the fulfillment of the divine purpose for humanity."
"Immanuel Kant (1724–1804) is the central figure in modern philosophy. He synthesized early modern rationalism and empiricism, set the terms for much of nineteenth and twentieth century philosophy, and continues to exercise a significant influence today in metaphysics, epistemology, ethics, political philosophy, aesthetics, and other fields. The fundamental idea of Kant’s 'critical philosophy' – especially in his three Critiques: the Critique of Pure Reason (1781, 1787), the Critique of Practical Reason (1788), and the Critique of the Power of Judgment (1790) – is human autonomy. He argues that the human understanding is the source of the general laws of nature that structure all our experience; and that human reason gives itself the moral law, which is our basis for belief in God, freedom, and immortality. Therefore, scientific knowledge, morality, and religious belief are mutually consistent and secure because they all rest on the same foundation of human autonomy, which is also the final end of nature according to the teleological worldview of reflecting judgment that Kant introduces to unify the theoretical and practical parts of his philosophical system."
