Primary Sources – Modern Philosophy


Three Dialogues Between Hylas and Philonous by George Berkeley – (Buy on Amazon)

Three Dialogues between Hylas and Philonous is a book written by George Berkeley in 1713. Three important concepts discussed in the Three Dialogues are perceptual relativity, the conceivability/master argument, and Berkeley’s phenomenalism. Perceptual relativity argues that the same object can appear to have different characteristics (e.g. shape) depending on the observer’s perspective. Since objective features of objects cannot change without an inherent change in the object itself, shape must not be an objective feature.


A Treatise Concerning the Principles of Human Knowledge by George Berkeley – (Buy on Amazon)

If a tree falls in the forest and no one is present to hear it, does it make a sound? It does not, according to George Berkeley. Originally published in 1710, this landmark of Western philosophy introduced a revolutionary concept: immaterialism, which asserts that to be is to perceive or be perceived. An Irish clergyman who spent his entire philosophical career as a churchman, Berkeley linked his investigations to his religious interests. A Treatise Concerning the Principles of Human Knowledge opens with an assault on Locke’s theory of abstract ideas and proceeds with arguments that sensible qualities exist only when perceived as ideas. Physical objects, he claims, are no more than collections of qualities, and these sensible objects, too, are merely ideas. Berkeley relates his position to the achievements of eighteenth-century science, and proclaims the compatibility of immaterialism with traditional religion. The fullest expression of Berkeley’s doctrine of immaterialism, this classic work influenced British philosophers from David Hume to Bertrand Russell and the other logical positivists. It is essential reading for all students of philosophy.


Discourse on the Method of Rightly Conducting the Reason and Seeking for Truth in the Sciences by René Descartes – (Buy on Amazon)

The Discourse on the Method is a philosophical and mathematical treatise published by René Descartes in 1637. This work is best known as the source of the famous quotation “Cogito, ergo sum” (“I think, therefore I am”), which occurs in Part IV of the work. The Discourse on the Method is one of the most influential works in the history of modern science. It is a method which gives a solid platform from which all modern natural sciences could evolve. In this work, Descartes tackles the problem of skepticism which had been revived from the ancients such as Sextus Empiricus by authors such as Algazel and Michel de Montaigne. Descartes modified it to account for a truth that he found to be incontrovertible. Descartes started his line of reasoning by doubting everything, so as to assess the world from a fresh perspective, clear of any preconceived notions.


Meditations on First Philosophy by René Descartes – (Buy on Amazon)

Meditations on First Philosophy, in which the existence of God and the immortality of the soul are demonstrated, is a philosophical treatise by René Descartes first published in Latin in 1641. The book is made up of six meditations, in which Descartes first discards all belief in things that are not absolutely certain, and then tries to establish what can be known for sure. He wrote the meditations as if he had meditated for six days: each meditation refers to the last one as “yesterday”. One of the most influential philosophical texts ever written, it is widely read to this day. The book consists of the presentation of Descartes’ metaphysical system in its most detailed level and in the expanding of his philosophical system, first introduced in the fourth part of his Discourse on Method (1637). Descartes’ metaphysical thought is also found in the Principles of Philosophy (1644), which the author intended to be a philosophy guidebook.


Democracy and Education by John Dewey – (Buy on Amazon)

John Dewey’s Democracy and Education addresses the challenge of providing quality public education in a democratic society. In this classic work, Dewey calls for the complete renewal of public education, arguing for the fusion of vocational and contemplative studies in education and for the necessity of universal education for the advancement of self and society. First published in 1916, Democracy and Education is regarded as the seminal work on public education by one of the most important scholars of the century.


Ideas and Opinions by Albert Einstein – (Buy on Amazon)

Ideas and Opinions contains essays by eminent scientist Albert Einstein on subjects ranging from atomic energy, relativity, and religion to human rights, government, and economics. Previously published articles, speeches, and letters are gathered here to create a fascinating collection of meditations by one of the world’s greatest minds.


Essays of Ralph Waldo Emerson – (Buy on Amazon)

Ralph Waldo Emerson was an American essayist, lecturer, philosopher, and poet who led the transcendentalist movement of the mid-19th century. He was seen as a champion of individualism and a prescient critic of the countervailing pressures of society, and he disseminated his thoughts through dozens of published essays and more than 1,500 public lectures across the United States. Emerson gradually moved away from the religious and social beliefs of his contemporaries, formulating and expressing the philosophy of transcendentalism in his 1836 essay “Nature“. Following this work, he gave a speech entitled “The American Scholar” in 1837, which Oliver Wendell Holmes Sr. considered to be America’s “intellectual Declaration of Independence.”


The Vocation of Man by Johann Gottlieb Fichte – (Buy on Amazon)

Johann Gottlieb Fichte (May 19, 1762 – January 27, 1814), was a German philosopher who became a founding figure of the philosophical movement known as German Idealism, which developed from the theoretical and ethical writings of Immanuel Kant. Recently, philosophers and scholars have begun to appreciate Fichte as an important philosopher in his own right due to his original insights into the nature of self-consciousness or self-awareness. Fichte was also the originator of thesis–antithesis–synthesis, an idea that is often erroneously attributed to Hegel. Like Descartes and Kant before him, Fichte was motivated by the problem of subjectivity and consciousness.


The Science of Knowledge by Johann Gottlieb Fichte – (Buy on Amazon)

The Foundations of the Science of Knowledge is a 1795 book by the German philosopher Johann Gottlieb Fichte, which contributed to the development of 19th-century German Idealism from Kant’s critical philosophy. Based on lectures Fichte had delivered as a Professor of Philosophy at the University of Jena, it was later reworked in various versions.


On Sense and Reference by Gottlob Frege – (Buy on Amazon)

In the philosophy of language, the distinction between sense and reference was an innovation of the German philosopher and mathematician Gottlob Frege in 1892, reflecting the two ways he believed a singular term may have meaning. The reference (or “referent”) of a proper name is the object it means or indicates, its sense is what the name expresses. The reference of a sentence is its truth value, its sense is the thought that it expresses. Frege justified the distinction in a number of ways. Much of analytic philosophy is traceable to Frege’s philosophy of language. Frege’s views on logic (i.e., his idea that some parts of speech are complete by themselves, and are analogous to the arguments of a mathematical function) led to his views on a theory of reference.


The Thought: A Logical Inquiry by Gottlob Frege – (Buy on Amazon)

Friedrich Ludwig Gottlob Frege (8 November 1848 – 26 July 1925) was a German philosopher, logician, and mathematician. He is understood by many to be the father of analytic philosophy, concentrating on the philosophy of language and mathematics. Though largely ignored during his lifetime, Giuseppe Peano (1858–1932) and Bertrand Russell (1872–1970) introduced his work to later generations of logicians and philosophers.

His contributions include the development of modern logic in the Begriffsschrift and work in the foundations of mathematics. His book the Foundations of Arithmetic is the seminal text of the logicist project, and is cited by Michael Dummett as where to pinpoint the linguistic turn. His philosophical papers “On Sense and Reference” and “The Thought” are widely cited.


The Phenomenology of Spirit by G.W.F. Hegel – (Buy on Amazon)

Perhaps one of the most revolutionary works of philosophy ever presented, The Phenomenology of Spirit is Hegel’s 1807 work that is in numerous ways extraordinary. It begins with a Preface, created after the rest of the manuscript was completed, that explains the core of his method and what sets it apart from any preceding philosophy. The Introduction, written before the rest of the work, summarizes and completes Kant’s ideas on skepticism by rendering it moot and encouraging idealism and self-realization. The body of the work is divided into six sections of varying length, entitled “Consciousness,” “Self-Consciousness,” “Reason,” “Spirit,” “Religion,” and “Absolute Knowledge.” A myriad of topics are discussed, and explained in such a harmoniously complex way that the method has been termed Hegelian dialectic. Ultimately, the work as a whole is a remarkable study of the mind’s growth from its direct awareness to scientific philosophy, proving to be a difficult yet highly influential and enduring work.


The Philosophy Of History (Introduction) by G. W. F. Hegel – (Buy on Amazon)

The Philosophy of History is a major work by Georg Wilhelm Friedrich Hegel (1770–1831), originally given as lectures at the University of Berlin in 1822, 1828, and 1830. It presents world history in terms of the Hegelian philosophy in order to show that history follows the dictates of reason and that the natural progress of history is due to the outworking of Absolute Spirit.


Philosophy Of Mind: Part Three of the Encyclopaedia of the Philosophical Sciences by G.W.F. Hegel – (Buy on Amazon)

From the Introduction: “The knowledge of Mind is the highest and hardest, just because it is the most ‘concrete’ of sciences. The significance of that ‘absolute’ commandment, Know thyself – whether we look at it in itself or under the historical circumstances of its first utterance – is not to promote mere selfknowledge in respect of the particular capacities, character, propensities, and foibles of the single self. The knowledge it commands means that of man’s genuine reality – of what is essentially and ultimately true and real – of mind as the true and essential being.”


Being and Time by Martin Heidegger – (Buy on Amazon)

Being and Time is a 1927 book by the German philosopher Martin Heidegger, in which the author seeks to analyse the concept of Being. Heidegger maintains that this has fundamental importance for philosophy and that, since the time of the Ancient Greeks, philosophy has avoided the question, turning instead to the analysis of particular beings. Heidegger attempts to revive ontology through a reawakening of the question of the meaning of Being. He approaches this through a fundamental ontology that is a preliminary analysis of the Being of the being to whom the question of Being is important, i.e., Dasein.

Heidegger wrote that Being and Time was made possible by his study of Edmund Husserl’s Logical Investigations (1900–1901), and it is dedicated to Husserl “in friendship and admiration”. It was immediately recognized as an original and groundbreaking philosophical work, and later became a focus of debates and controversy, and a profound influence on 20th-century philosophy, particularly existentialism, hermeneutics, deconstruction, and the enactivist approach to cognition. Being and Time has been described as the most influential version of existential philosophy, and Heidegger’s achievements in the work have been compared to those of Immanuel Kant in the Critique of Pure Reason (1781) and Georg Wilhelm Friedrich Hegel in The Phenomenology of Spirit (1807) and Science of Logic (1812–1816). The work influenced philosophical treatises such as Jean-Paul Sartre’s Being and Nothingness (1943).


The Question Concerning Technology & Other Essays by Martin Heidegger – (Buy on Amazon)

The first pages of The Question Concerning Technology set the terms of Heidegger’s discussion. The first paragraph establishes the essay’s objective: to investigate technology in order to prepare us for a “free relationship” to it. One of the fundamental questions of the essay has to do with how we currently relate to technology, how we think about it, what we imagine it to be.

The problem for Heidegger is not so much the existence of technology or the forms it takes, but rather our orientation to technology. If we accept this formulation of the problem, then it becomes clear that our response to the various problems brought about by technology cannot be solved simply by making the technology better. It is also impossible to ignore these difficulties simply by “opting out” of technology.


What is Metaphysics? by Martin Heidegger – (Buy on Amazon)

According to Heidegger, the fundamental question of metaphysics is “why are there beings at all instead of nothing?” From this fundamental question Heidegger extracts a prior question about the relation to Being; or “How does it stand with Being?” This is to be answered through an analysis of Greek poetry, the etymology of the word being and of the answers given by philosophers such as Parmenides, Heraclitus, Aristotle, and Immanuel Kant. To Heidegger, this question is not purely an academic endeavour, for metaphysics grounds an age, by giving “that age the basis upon which it is essentially formed”. The question thus inherently implicates the totality of human Dasein, and is asked so as to “restore the historical Dasein of human beings … back to the power of Being that is to be opened up originally”. This opens up the discussion of socio-political entanglements of Dasein and Heidegger’s notion of the “inner truth and greatness” of National Socialism.


Dialogues Concerning Natural Religion by David Hume – (Buy on Amazon)

Dialogues Concerning Natural Religion is a philosophical work by the Scottish philosopher David Hume. Through dialogue, three philosophers named Demea, Philo, and Cleanthes debate the nature of God’s existence. Whether or not these names reference specific philosophers, ancient or otherwise, remains a topic of scholarly dispute. While all three agree that a god exists, they differ sharply in opinion on God’s nature or attributes and how, or if, humankind can come to knowledge of a deity.

In the Dialogues, Hume’s characters debate a number of arguments for the existence of God, and arguments whose proponents believe through which we may come to know the nature of God. Such topics debated include the argument from design—for which Hume uses a house—and whether there is more suffering or good in the world (the argument from evil).


An Enquiry Concerning Human Understanding by David Hume – (Buy on Amazon)

An Enquiry Concerning Human Understanding is a revision of an earlier effort, Hume’s A Treatise of Human Nature, published anonymously in London in 1739–40. Hume was disappointed with the reception of the Treatise, which “fell dead-born from the press,” as he put it, and so tried again to disseminate his more developed ideas to the public by writing a shorter and more polemical work.

The end product of his labours was the Enquiry. The Enquiry dispensed with much of the material from the Treatise, in favor of clarifying and emphasizing its most important aspects. For example, Hume’s views on personal identity do not appear. However, more vital propositions, such as Hume’s argument for the role of habit in a theory of knowledge, are retained.

This book has proven highly influential, both in the years that would immediately follow and today. Immanuel Kant points to it as the book which woke him from his self-described “dogmatic slumber.” The Enquiry is widely regarded as a classic in modern philosophical literature.


An Enquiry Concerning the Principles of Morals by David Hume – (Buy on Amazon)

In An Enquiry Concerning the Principles of Morals, Hume argues (among other things) that the foundations of morals lie with sentiment, not reason.

An Enquiry Concerning the Principles of Morals is the enquiry subsequent to the Enquiry Concerning Human Understanding. Thus, it is often referred to as “the second Enquiry”. It was originally published in 1751, three years after the first Enquiry. Hume first discusses ethics in A Treatise of Human Nature (in Book 3 – “Of Morals”). He later extracted and expounded upon the ideas he proposed there in his second Enquiry. In his short autobiographical work, My Own Life (1776), Hume states that his second Enquiry is “of all my writings, historical, philosophical, or literary, incomparably the best.”


A Treatise of Human Nature by David Hume – (Buy on Amazon)

Considered by many to be Hume’s most important work and one of the most influential works in the history of philosophy, The Treatise is a classic statement of philosophical empiricism, skepticism, and naturalism. In the introduction, Hume presents the idea of placing all science and philosophy on a novel foundation: namely, an empirical investigation into human nature. Impressed by Isaac Newton’s achievements in the physical sciences, Hume sought to introduce the same experimental method of reasoning into the study of human psychology, with the aim of discovering the “extent and force of human understanding”. Against the philosophical rationalists, Hume argues that passion rather than reason governs human behaviour. He introduces the famous problem of induction, arguing that inductive reasoning and our beliefs regarding cause and effect cannot be justified by reason; instead, our faith in induction and causation is the result of mental habit and custom. Hume defends a sentimentalist account of morality, arguing that ethics is based on sentiment and passion rather than reason, and famously declaring that “reason is, and ought only to be the slave to the passions”. Hume also offers a skeptical theory of personal identity and a compatibilist account of free will.


Practical Philosophy of Immanuel Kant – (Buy on Amazon)

This is the first English translation of all of Kant’s writings on moral and political philosophy collected in a single volume. No other collection competes with the comprehensiveness of this one. As well as Kant’s most famous moral and political writings, the Groundwork to the Metaphysics of Morals, the Critique of Practical Reason, the Metaphysics of Morals, and Toward Perpetual Peace, the volume includes shorter essays and reviews, some of which have never been translated before. The volume has been furnished with a substantial editorial apparatus including translator’s introductions and explanatory notes to each text by Mary Gregor, and a general introduction to Kant’s moral and political philosophy by Allen Wood. There is also an English-German and German-English glossary of key terms.


The Critique of Pure Reason by Immanuel Kant – (Buy on Amazon)

The Critique of Pure Reason is a 1781 book by the German philosopher Immanuel Kant, in which the author seeks to determine the limits and scope of metaphysics. A heavily-revised second edition was published in 1787. Also referred to as Kant’s “First Critique,” it was followed by the Critique of Practical Reason (1788) and the Critique of Judgment (1790). In the preface to the first edition, Kant explains that by a “critique of pure reason” he means not “a critique of books and systems, but of the faculty of reason in general, in respect of all knowledge after which it may strive independently of all experience” and that he aims to reach a decision about “the possibility or impossibility of metaphysics”. The First Critique is often viewed as culminating several centuries of early-modern philosophy, and inaugurating modern philosophy.


The Critique of Practical Reason by Immanuel Kant – (Buy on Amazon)

The Critique of Practical Reason is the second of Immanuel Kant’s three critiques, published in 1788. It follows on from Kant’s Critique of Pure Reason and deals with his moral philosophy. The second Critique exercised a decisive influence over the subsequent development of the field of ethics and moral philosophy, beginning with Johann Gottlieb Fichte’s Doctrine of Science and becoming, during the 20th century, the principal reference point for deontological moral philosophy.


The Critique of Judgement by Immanuel Kant – (Buy on Amazon)

Immanuel Kant’s Critique of Judgment completes the Critical project begun in the Critique of Pure Reason and the Critique of Practical Reason (the First and Second Critiques, respectively). The book is divided into two main sections: the Critique of Aesthetic Judgment and the Critique of Teleological Judgment, and also includes a large overview of the entirety of Kant’s Critical system, arranged in its final form.

The Critical project, that of exploring the limits and conditions of knowledge, had already produced the Critique of Pure Reason, in which Kant argued for a Transcendental Aesthetic, an approach to the problems of perception in which space and time are argued not to be objects but ways in which the observing subject’s mind organizes and structures the sensory world. The end result of this inquiry is that there are certain fundamental antinomies in human Reason, most particularly that there is a complete inability to favor on the one hand the argument that all behavior and thought is determined by external causes, and on the other that there is an actual “spontaneous” causal principle at work in human behavior.


Introduction to the Metaphysics of Morals by Immanuel Kant – (Buy on Amazon)

The Metaphysics of Morals is Kant’s major work in applied moral philosophy in which he deals with the basic principles of rights and of virtues. It comprises two parts: the ‘Doctrine of Right’, which deals with the rights which people have or can acquire, and the ‘Doctrine of Virtue’, which deals with the virtues they ought to acquire.


Fundamental Principles of the Metaphysics of Morals by Immanuel Kant – (Buy on Amazon)

The Fundamental Principles of the Metaphysics of Morals is the first of Immanuel Kant’s mature works on moral philosophy and remains one of the most influential in the field. Kant conceives his investigation as a work of foundational ethics—one that clears the ground for future research by explaining the core concepts and principles of moral theory and showing that they are normative for rational agents. Kant aspires to nothing less than this: to lay bare the fundamental principle of morality and show that it applies to us. In the text, Kant provides a groundbreaking argument that the rightness of an action is determined by the character of the principle that a person chooses to act upon. Kant thus stands in stark contrast to the moral sense theories and teleological moral theories that dominated moral philosophy at the time he was writing. Central to the work is the role of what Kant refers to as the categorical imperative, the concept that one must act only according to that precept which he or she would will to become a universal law.


Prolegomena to any Future Metaphysics by Immanuel Kant – (Buy on Amazon)

Prolegomena to Any Future Metaphysics That Will Be Able to Present Itself as a Science is a book by the German philosopher Immanuel Kant, published in 1783, two years after the first edition of his Critique of Pure Reason. One of Kant’s shorter works, it contains a summary of the Critique‘s main conclusions, sometimes by arguments Kant had not used in the Critique. Kant characterizes his more accessible approach here as an “analytic” one, as opposed to the Critique‘s “synthetic” examination of successive faculties of the mind and their principles.

The book is also intended as a polemic. Kant was disappointed by the poor reception of the Critique of Pure Reason, and here he repeatedly emphasizes the importance of its critical project for the very existence of metaphysics as a science. The final appendix contains a detailed rebuttal to an unfavorable review of the Critique.


Fear and Trembling by Søren Kierkegaard – (Buy on Amazon)

Fear and Trembling is a philosophical work by Søren Kierkegaard, published in 1843 under the pseudonym Johannes de Silentio (John of the Silence). The title is a reference to a line from Philippians 2:12, “…continue to work out your salvation with fear and trembling.” — itself a probable reference to Psalms 55:5,[1] “Fear and trembling came upon me…”

Kierkegaard wanted to understand the anxiety that must have been present in Abraham when “God tested [him] and said to him, take Isaac, your only son, whom you love, and go to the land of Moriah and offer him as a burnt offering on the mountain that I shall show you.” Abraham had a choice to complete the task or to refuse to comply with God’s orders. He resigned himself to the three-and-a-half-day journey and to the loss of his son. “He said nothing to Sarah, nothing to Eliezer. Who, after all, could understand him, for did not the nature of temptation extract from him a pledge of silence? He split the firewood, he bound Isaac, he lit the fire, he drew the knife.” Because he kept everything to himself and chose not to reveal his feelings he “isolated himself as higher than the universal.” Kierkegaard envisions two types of people in Fear and Trembling and Repetition. One lives in hope, Abraham, the other lives in memory, The Young Man and Constantin Constantius.


The Sickness Unto Death by Søren Kierkegaard – (Buy on Amazon)

The Sickness Unto Death is a book written by Danish philosopher Søren Kierkegaard in 1849 under the pseudonym Anti-Climacus. A work of Christian existentialism, the book is about Kierkegaard’s concept of despair, which he equates with the Christian concept of sin, particularly original sin. The Sickness Unto Death has strong existentialist themes. For example, the concept of the finite and infinite parts of the human self translate to Heidegger’s concept of ‘facticity’ and Sartre’s concept of ‘transcendence’ in Being and Nothingness. Kierkegaard’s thesis is, of course, in other ways profoundly different from Sartre, most obviously because of Kierkegaard’s belief that only religious faith can save the soul from despair.


Philosophical Fragments by Søren Kierkegaard – (Buy on Amazon)

Philosophical Fragments is a Christian philosophical work written by Danish philosopher Søren Kierkegaard in 1844. It was the second of three works written under the pseudonym Johannes Climacus. Kierkegaardian scholars D. Anthony Storm and Walter Lowrie believe Kierkegaard could be referring to Johannes Climacus, a 7th-century Christian monk, who believed that an individual is converted to Christianity by way of a ladder, one rung (virtue) at a time. Kierkegaard believes the individual comes to an understanding with Christ by a leap. Kierkegaard wrote his books in reaction to both Georg Wilhelm Friedrich Hegel and Karl Wilhelm Friedrich Schlegel as well as the philosophic-historical use of speculation in regard to Christianity.


Concluding Unscientific Postscript to Philosophical Fragments by Søren Kierkegaard – (Buy on Amazon)

This work is a poignant attack against Hegelianism, the philosophy of Hegel, especially Hegel’s Science of Logic. The work is also famous for its dictum, Subjectivity is Truth. It was an attack on what Kierkegaard saw as Hegel’s deterministic philosophy. Against Hegel’s system, Kierkegaard is often interpreted as taking the side of metaphysical libertarianism or free will, though it has been argued that an incompatibilist conception of free will is not essential to Kierkegaard’s formulation of existentialism.

As the title suggests, the Postscript is a sequel to the earlier Philosophical Fragments. The title of the work is ironic because the Postscript is almost five times larger than the Fragments. The Postscript credits “Johannes Climacus” as the author and Kierkegaard as its editor. Like his other pseudonymous works, the Postscript is not a reflection of Kierkegaard’s own beliefs. However, unlike his other pseudonymous works, Kierkegaard attaches his name as editor to this work, showing the importance of the Postscript to Kierkegaard’s overall authorship.


Monadology by Gottfried Wilhelm Leibniz – (Buy on Amazon)

The Monadology (1714) is one of Gottfried Leibniz’s best-known works representing his later philosophy. It is a short text which sketches in some 90 paragraphs a metaphysics of simple substances, or monads. The monad, the word and the idea, belongs to the Western philosophical tradition and has been used by various authors. Leibniz, who was exceptionally well read, could not have ignored this, but he did not use it himself until mid-1696 when he was sending for print his New System. Apparently, he found with it a convenient way to expose his own philosophy as it was elaborated in this period. What he proposed can be seen as a modification of occasionalism developed by latter-day Cartesians. Leibniz surmised that there are indefinitely many substances individually ‘programmed’ to act in a predetermined way, each substance being coordinated with all the others. This is the pre-established harmony which solved the mind-body problem, but at the cost of declaring any interaction between substances a mere appearance.


An Essay Concerning Human Understanding by John Locke – (Buy on Amazon)

An Essay Concerning Human Understanding (1690) is a work by John Locke concerning the foundation of human knowledge and understanding. He describes the mind at birth as a blank slate (tabula rasa, although he did not use those actual words) filled later through experience. The essay was one of the principal sources of empiricism in modern philosophy and influenced many enlightenment philosophers, such as David Hume and George Berkeley.

Book I of the Essay is Locke’s attempt to refute the rationalist notion of innate ideas. Book II sets out Locke’s theory of ideas, including his distinction between passively acquired simple ideas, such as “red,” “sweet,” “round,” etc., and actively built complex ideas, such as numbers, causes and effects, abstract ideas, ideas of substances, identity, and diversity. Locke also distinguishes between the truly existing primary qualities of bodies, like shape, motion and the arrangement of minute particles, and the secondary qualities that are “powers to produce various sensations in us” such as “red” and “sweet.” These secondary qualities, Locke claims, are dependent on the primary qualities. He also offers a theory of personal identity, offering a largely psychological criterion. Book III is concerned with language, and Book IV with knowledge, including intuition, mathematics, moral philosophy, natural philosophy (“science”), faith, and opinion.


Utilitarianism by John Stuart Mill – (Buy on Amazon)

John Stuart Mill’s book Utilitarianism is a classic exposition and defence of utilitarianism in ethics. The essay first appeared as a series of three articles published in Fraser’s Magazine in 1861; the articles were collected and reprinted as a single book in 1863. Mill’s aim in the book is to explain what utilitarianism is, to show why it is the best theory of ethics, and to defend it against a wide range of criticisms and misunderstandings. Though heavily criticized both in Mill’s lifetime and in the years since, Utilitarianism did a great deal to popularize utilitarian ethics and has been considered “the most influential philosophical articulation of a liberal humanistic morality that was produced in the nineteenth century.”


Principia Ethica by G.E. Moore – (Buy on Amazon)

Principia Ethica is a 1903 book by the British philosopher G. E. Moore, in which the author insists on the indefinability of “good” and provides an exposition of the naturalistic fallacy. Principia Ethica was influential, and Moore’s arguments were long regarded as path-breaking advances in moral philosophy, though they have been seen as less impressive and durable than his contributions in other fields.

Moore insists that “good” is indefinable, and provides an exposition of what he calls the “naturalistic fallacy.” He defends the objectivity and multiplicity of values, arguing that knowledge of values cannot be derived from knowledge of facts, but only from intuition of the goodness of such states of affairs as beauty, pleasure, friendship and knowledge. In Moore’s view, right acts are those producing the most good.


On the Genealogy of Morals by Friedrich Nietzsche – (Buy on Amazon)

On the Genealogy of Morals is an 1887 book by German philosopher Friedrich Nietzsche. It consists of a preface and three interrelated essays that expand and follow through on concepts Nietzsche sketched out in Beyond Good and Evil (1886). The three essays trace episodes in the evolution of moral concepts with a view to confronting “moral prejudices”, specifically those of Christianity and Judaism. Some Nietzsche scholars consider Genealogy to be a work of sustained brilliance and power as well as his masterpiece. Since its publication, it has influenced many authors and philosophers.


The Portable Nietzsche edited by Walter Kaufmann – (Buy on Amazon)

The philosopher Friedrich Nietzsche was born in Prussia in 1844. After the death of his father, a Lutheran minister, Nietzsche was raised from the age of five by his mother in a household of women. In 1869 he was appointed Professor of Classical Philology at the University of Basel, where he taught until 1879 when poor health forced him to retire. He never recovered from a nervous breakdown in 1889 and died eleven years later. Known for saying that “God is dead,” Nietzsche propounded his metaphysical construct of the superiority of the disciplined individual (Super-man) living in the present over traditional values derived from Christianity and its emphasis on heavenly rewards. His ideas were appropriated by the Fascists, who turned his theories into social realities that he had never intended.

As Walter Kaufmann, one of the world’s leading authorities on Nietzsche, notes in his introduction, “Few writers in any age were so full of ideas,” and few writers have been so consistently misinterpreted. The Portable Nietzsche includes Kaufmann’s definitive translations of the complete and unabridged texts of Nietzsche’s four major works: Twilight of the Idols, The Antichrist, Nietzsche Contra Wagner and Thus Spoke Zarathustra. In addition, Kaufmann brings together selections from his other books, notes, and letters, to give a full picture of Nietzsche’s development, versatility, and inexhaustibility.


Thus Spake Zarathustra by Friedrich Nietzsche – (Buy on Amazon)

Thus Spake Zarathustra is incomplete, but it is the first thorough statement of Nietzsche’s mature philosophy and the masterpiece of his career. It received little attention during his lifetime but its influence since his death has been considerable, in the arts as well as philosophy. Written in the form of a prose narrative, Thus Spake Zarathustra offers the philosophy of its author through the voice of Zarathustra (based on the Persian prophet Zoroaster) who, after years of meditation, has come down from a mountain to offer his wisdom to the world. It is this work in which Nietzsche made his famous (and much misconstrued) statement that “God is dead” and in which he presented some of the most influential and well-known (and likewise misunderstood) ideas of his philosophy, including those of the Ubermensch (“overman” or “superman”) and the “will to power.” Though this is essentially a work of philosophy, it is also a masterpiece of literature. The book is a combination of prose and poetry, including epigrams, dithyrambs, and parodies as well as sections of pure poetry.


The Age of Reason by Thomas Paine – (Buy on Amazon)

The Age of Reason is an influential work by Thomas Paine that follows in the tradition of eighteenth-century British deism, and challenges institutionalized religion and the legitimacy of the Bible. It presents common deistic arguments; for example, it highlights what Paine saw as corruption of the Christian Church and criticizes its efforts to acquire political power. Paine advocates reason in the place of revelation, leading him to reject miracles and to view the Bible as “an ordinary piece of literature rather than as a divinely inspired text”. It promotes natural religion and argues for the existence of a creator-God. The Age of Reason is divided into three sections. In Part I, Paine outlines his major arguments and personal creed. In Parts II and III he analyzes specific portions of the Bible in order to demonstrate that it is not the revealed word of God. Most of Paine’s arguments had long been available to the educated elite, but by presenting them in an engaging and irreverent style, he made deism appealing and accessible to a mass audience.


Pensées by Blaise Pascal – (Buy on Amazon)

The Pensées (“Thoughts”) is a collection of fragments on theology and philosophy written by 17th-century philosopher and mathematician Blaise Pascal. Pascal’s religious conversion led him into a life of asceticism, and the Pensées was in many ways his life’s work. The Pensées represented Pascal’s defense of the Christian religion. The concept of “Pascal’s Wager” stems from a portion of this work.


The Fixation of Belief by Charles Sanders Peirce – (Buy on Amazon)

Charles Sanders Pierce (1839-1914) was an American philosopher, logician, mathematician, and scientist who is sometimes known as “the father of pragmatism”. He was educated as a chemist and employed as a scientist for 30 years. Today he is appreciated largely for his contributions to logic, mathematics, philosophy, scientific methodology, and semiotics, and for his founding of pragmatism.

Peirce argued that the aim of inquiry is the fixation of belief, and that the scientific method is the most effective way of so doing. The purpose of inquiry is to move from doubt to belief. Belief is a mental state in which there is no doubt. A belief may cease to be held and lead back to discomfort in the (former) believer, so the best kind of belief is the settled and stable kind. Inquiry itself is the struggle to attain belief. There are many methods used to attain belief and some are better than others.


How to Make Our Ideas Clear by Charles Sanders Peirce – (Buy on Amazon)

How to Make Our Ideas Clear is the cornerstone for the philosophical school now known as pragmatism and began the formalization of the scientific method. It is justly regarded as one of the most important philosophical papers ever written.


The Confessions of Jean-Jacques Rousseau – (Buy on Amazon)

Jean-Jacques Rousseau (1712-1778) was a Genevan philosopher, writer and composer. Born in Geneva, his political philosophy influenced the progress of the Enlightenment throughout Europe, as well as aspects of the French Revolution and the development of modern political and educational thought. His Discourse on Inequality and The Social Contract are cornerstones in modern political and social thought.

The Confessions is an autobiographical book by Rousseau. In modern times, it is often published with the title The Confessions of Jean-Jacques Rousseau in order to distinguish it from Saint Augustine’s Confessions. Covering the first fifty-three years of Rousseau’s life, up to 1765, it was completed in 1769, but not published until 1782, four years after Rousseau’s death.


The World as Will and Representation – Vol. 1 by Arthur Schopenhauer – (Buy on Amazon)

The World as Will and Representation – Vol. 2 by Arthur Schopenhauer – (Buy on Amazon)

Arthur Schopenhauer (1788-1860) was a German philosopher. He is best known for his 1818 work The World as Will and Representation (expanded in 1844), wherein he characterizes the phenomenal world as the product of a blind and insatiable metaphysical will. Proceeding from the transcendental idealism of Immanuel Kant, Schopenhauer developed an atheistic metaphysical and ethical system that has been described as an exemplary manifestation of philosophical pessimism, rejecting the contemporaneous post-Kantian philosophies of German idealism. Schopenhauer was among the first thinkers in Western philosophy to share and affirm significant tenets of Eastern philosophy (e.g., asceticism, the world-as-appearance), having initially arrived at similar conclusions as the result of his own philosophical work.

Though his work failed to garner substantial attention during his life, Schopenhauer has had a posthumous impact across various disciplines, including philosophy, literature, and science. His writing on aesthetics, morality, and psychology influenced thinkers and artists throughout the 19th and 20th centuries. Those who cited his influence include Friedrich Nietzsche, Richard Wagner, Leo Tolstoy, Ludwig Wittgenstein, Erwin Schrödinger, Otto Rank, Gustav Mahler, Joseph Campbell, Albert Einstein, Carl Jung, Thomas Mann, Émile Zola, George Bernard Shaw, Jorge Luis Borges and Samuel Beckett.


The Basis of Morality by Arthur Schopenhauer – (Buy on Amazon)

The Basis of Morality is one of Arthur Schopenhauer’s major works in ethics, in which he argues that morality stems from compassion. Schopenhauer begins with a criticism of Kant’s Groundwork of the Metaphysic of Morals, which Schopenhauer considered to be the clearest explanation of Kant’s foundation of ethics. On the Basis of Morality is divided into four sections. The first section is an introduction in which Schopenhauer provides his account of the question posed by the Royal Danish Society and his interpretation of the history of western ethics. In the second section, Schopenhauer embarks on a criticism of Kant’s foundation of ethics. The third section of the work is Schopenhauer’s positive construction of his own ethical theory. The final section of the work provides a brief description of the metaphysical foundations of ethics.


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