100 Great Philosophers Who Changed the World

Philip Stokes

• Publisher: Arcturus
• Year: 2021
• ISBN:
  9781398806160
• Topic: Philosophy
• Subtopic: Philosophy History & Theory

Who am I? What is justice? What does it mean to live a good life? Fully illustrated throughout, this engaging and accessible hardback book invites readers to contemplate the ideas of 100 key philosophers within the Western intellectual tradition. Covering philosophical, scientific, political and religious thought over a period of 2500 years, 100 Great Philosophers W ho Changed the World serves as an excellent guide to this history of philosophy and the progress that has been made in interpreting the world around us.These figures include:
• Aristotle
• Jean-Jacques Rousseau
• Karl Marx
• Simone de Beauvoir
• Noam Chomsky
• W.V.O QuineBy presenting details of their lives and the concerns and circumstances that motivated them, this book makes philosophy come to life as a relevant and meaningful approach to thinking about the contemporary world.

Gottlob Frege

1848–1925

The meaning of a term can only be given in the context of a sentence

German philosopher whose work went unnoticed in his own lifetime, Gottlob Frege has become one of the greatest influences on twentieth century philosophy for his work in logic and the philosophy of mathematics. That philosophy took the so-called ‘linguistic turn’ – the prefacing of ontological and metaphysical reflections with a prior analysis of how such commitments arise in language – is largely due to Frege. His invention of ‘quantificational’ logic was the greatest development in that subject since Aristotle and has completely replaced Aristotelian ‘syllogistic’ logic on university courses.

Frege’s contributions to modern philosophy and logic begin with his rejection of the Aristotelian analysis of sentences as being fundamentally of subject/predicate form. According to the classical analysis, a sentence such as ‘Socrates is wise’ can be analysed into two distinct parts. First, the subject of the sentence, ‘Socrates’, and second a property ascribed to the subject, namely ‘being wise’. This had been the received wisdom for over two thousand years and gave rise to some notoriously intractable philosophical puzzles, not least concerning the notion of substance and the ontological status of universals and particulars.

Frege swept all this away by analysing sentences on a mathematical model of function and argument. On his view, the sentence ‘Socrates is wise’ contains a function, ‘( ) is wise’, with ‘Socrates’ taking the place of argument for that function; in other words, filling the gap in the incomplete functional expression, ‘( ) is wise’. This view is taken over directly from mathematics, where sentences such as ‘2 + 3’ may be analysed in terms of a function ‘( ) + ( )’ being completed by the arguments ‘2’ and ‘3’.

This allowed Frege to inaugurate some profound developments in the philosophy of language. Since neither the functional expression nor the argument assert anything individually, but only when they are combined to form a complete expression, it follows that the meaning of a term can only be given in the context of the sentence (Frege’s ‘context principle’), by deducing what contribution it makes to the sense of the whole expression (‘the compositionality of meaning’). This combined thesis has been Frege’s most enduring legacy to the philosophy of language.

Having argued that meaning is now primarily a property of sentences, and only derivatively of terms, Frege could then apply a distinction in meaning between the sense and reference of an expression. Respectively, these are the thought the sentence expresses and the objects being referred to or talked about by the sentence. For instance, it is clear that ‘the leader of the Labour party’ and ‘the current Prime Minister’ are talking about, or referring to, one and the same person (just so long as the Labour party are in government). It is equally clear, however, that the two expressions express different ideas. Being leader of the Labour party is not the same thing as being the Prime Minister.

The sense/reference distinction has become a centre-piece of many modern theories of meaning. It lies at the heart of philosophical projects which try to show how language is connected to reality. Since, according to Frege, the sense of an expression determines what it refers to, it has seemed to some philosophers that there must be some essential connection between what we say and what there is. This is the idea that informed the logical atomism of both Bertrand Russell and the young Ludwig Wittgenstein (a view Wittgenstein would later reject), and continues to feature in a number of important contemporary philosophical programs.

Bertrand Russell

1872–1970

[Russell’s] theory of definite descriptions has become a standard tool of logical analysis

Britain’s most famous modern philosopher, whose magisterial History of Western Philosophy is still a classic of its kind. Russell first became famous for his attempt, only partially successful, to show how mathematics was grounded in logic. Despite eventually abandoning that project, he became famous within philosophy for his work in logical analysis and, in later life, in society for his humanist social philosophy. Interestingly Russell saw no essential connection between these two strands of his thought, claiming of his latter views, ‘On these questions I did not write in my capacity as a philosopher; I wrote as a human being who suffered from the state of the world, wished to find some way of improving it, and was anxious to speak in plain terms to others who had similar feelings’. Critics might complain that this, rather than his formal work in logical analysis, is surely the task of philosophy, but it is not a view Russell would share.

The scope of Russell’s work spans all the traditional areas of philosophy and incorporates many of the new ideas generated in the first half of the twentieth century. His thought continued to change and develop throughout his life. However, it is generally held that his most important contributions came in the first decade or so of the new century.

Concerned with the semantic problems of meaning and reference, Russell solved a longstanding philosophical conundrum with his famous ‘theory of definite descriptions’. The conundrum is generated out of considering whether to call a sentence true or false when it fails to refer. For example, consider:

The present King of France is bald.

Since there is no such person as ‘the present King of France’, do sentences of this kind count as false, or meaningless? Either view creates problems. To say it is meaningless defies the very simple fact that one can understand what the sentence is trying to assert. But to say it is false, seems to entail that the contradiction of (1), namely

The present King of France is not bald,

is true. But (2) is no more true than (1). So how do we settle the analysis of sentences that fail to refer in this way? Russell’s answer was ingenious. He proposed that such sentences are really descriptions which consist of a conjunction of separate claims. Namely, first, that there is some person who is the King of France, second, that there is only one person who is the King of France, and thirdly that any person that is the King of France is bald. Now these propositions can be formally decided. For they amount to a conjunction in which the first proposition is false (that there is a King of France). Logically, any statement that is a conjunction of propositions is false if any one of the conjuncts is false. Accordingly, the conjunction turns out false regardless of whether the other conjuncts are treated as true or false.

The theory of definite descriptions, in showing how it is possible to speak meaningfully of things that do not exist, has become a standard tool of logical analysis. It is essential to all those whose work in the philosophy of language is predicated on theories of meaning which seek to essentially connect the meaning of words with items in the world. For if that is the underlying basis of meaning, assertions about non-existents are surely problematic without Russell’s analysis.

Ludwig Wittgenstein

1889–1951

Raised in a prominent Viennese family, Ludwig Wittgenstein studied engineering in Germany and England, but became interested in the foundations of mathematics and pursued philosophical studies with Russell and Frege before entering the Austrian army during the First World War. The notebooks he kept as a soldier became the basis for his Tractatus Logico-Philosophicus (1922), which later earned him a doctorate from Cambridge and exerted a lasting influence on the philosophers of the Vienna Circle. Despite being only 32 when it was published, he declared that in it he had solved all the problems of philosophy and promptly retired from academic life.

The central concern of the Tractatus is the relationship between language, thought and reality. Language, Wittgenstein insists, is the perceptible form of thought and bound to reality by a common logical form or structure. Following Frege, Wittgenstein insisted that the meaning of linguistic expressions must be determined by the nature of the world, since otherwise the meaning or sense of an expression would be infected with vagueness and uncertainty. From Russell, he borrowed the idea that both language and the world must be understood in terms of their constituent or atomic parts. However, Wittgenstein broke away from his teachers by arguing that the underlying logical structure of sentences must exactly mirror or picture the essential structure of the world. This became known as his ‘picture theory’ of meaning: sentences are representations – literally pictures – of possible states of affairs. Since logical order is necessary for sense, Wittgenstein claimed, ordinary language could not be logically imperfect as both Russell and Frege had thought. On the contrary, claimed Wittgenstein, language is in order as it is, anything that can be said at all can be said clearly and what cannot be said clearly must be passed over in silence.

Meaning cannot be divorced from the activities and behaviour of the language users

After publication of the Tractatus, Wittgenstein went into self-imposed exile, giving away his inherited fortune and living and working in Austria, first as a schoolteacher and later as a gardener. By 1929, however, he had become unhappy with elements of his early work and returned to Cambridge. Meanwhile, in his absence the Tractatus had won critical acclaim and was beginning to exert major influence in European schools of thought. Wittgenstein now found himself in the unusual position of being the most vehement critic of his own early work. He spent the following 20 years till the end of his life trying to clarify and dispel the philosophical confusions that had informed his early thinking. The corpus of his later writings were published posthumously as Philosophical Investigations (1952).

In the Investigations Wittgenstein remains concerned with the nature of language, thought and reality. Now, however, he repudiates both the claim that meaning is dependent on reality and that language is essentially concerned with representation. Objects are not literally the meanings of names, rather they serve as elucidations of meaning – pointing to a table helps explain what the word ‘table’ means. Likewise, Wittgenstein realized, language has many functions. Words are like instruments or tools that we employ for many different purposes in different contexts. Language is not just used to represent or describe, but also to ask questions, play games, give orders, throw insults and so on. What a word means depends both on what it is being used to do and the context in which it is employed. This gives rise to Wittgenstein’s famous notion of ‘a language-game’: roughly, that it is the context which explains the meaning of an expression used in particular circumstances. The essence of Wittgenstein’s later work is that it is a mistake to conceive of meaning as essentially tied to the nature of reality. Meaning cannot be divorced from the activities and behaviour of language users, which both reflect and explain the meaning of our words.

It is hard to overestimate Wittgenstein’s influence on modern philosophy. His later work had a direct influence on J. L. Austin and the Oxford ‘ordinary language’ school of philosophy as well as the modern speech-act theorists. The assumptions present in and worked out through his early work, on the other hand, are still enshrined in the modern philosophical programs offered by Quine, Donald Davidson and Michael Dummett, to name just a few.

Ferdinand de Saussure

1857–1913

Swiss philologist whose work has had a monumental impact, first on linguistics and second – through the advent of the ‘linguistic turn’ – on philosophy. Saussure published little of wide interest during his lifetime, but in the last years of his life taught general linguistics at the University in Geneva. It is said that Saussure destroyed his notes after each lecture and thus, upon his death, left little work to indicate his ideas. Fortunately, his lectures were so extraordinary that his students collected and collated their notes over the three years he taught the course, and published them in 1916, as Cours de linguistique générale (A Course in General Linguistics), often simply referred to as the Cour...