Mike MackusOctober 16th 2008

Frege’s Distinction between Sense and Thought

In “The Thought: A Logical Inquiry,” Frege provides terms and vocabulary in order to

account for a number of problems in the philosophy of language. While the terminology Frege

introduces specifically helps to address the relationship between sign, meaning and referent, his

exposition is written always with the notion of truth in the background- a concept that he

continually grapples with to define. But in order to understand how Frege accounts for truth and

its relationship to thoughts and language we must come full circle, for as Frege discovers, there

is no non-circular way to define truth. The characteristic of being true is a not a relational one

such as the property of being red or the attribute of being tall. If one were to attempt to define

true then he must state characteristics of truth; this proves futile as it is only the case that

something is true if it is true that it has those characteristics.

With this problem at hand, Frege uses the idea of thought as an intermediary between a

linguistic sentence and its referent. First, however, we must examine Frege’s notion of sense

before we are able to understand the abstract existence of a thought. In order to deal with his

puzzle, Frege realized that there must be some way that two different linguistic expressions can

refer to the same object. He understands his puzzle as occurring simply by a difference in the

mode of presentation. Given that two different presentations, or two different senses, lead back

to the same referent, it is logical to conclude that the connection between the linguistic sign and

the sense is one of pure convention. However, this arbitrary connection does not imply the same

for the connection between sense and referent. Sense and referent are determined uniquely for

when we hear or read a linguistic expression we grasp its sense. Senses do not exist within any

specific individual, but rather they are communal. If senses were determined by one person then

there would be no shared understanding, no successful communication.

If we are to understand sense as the abstract objects by which we come to understand

certain linguistic expressions, then thoughts are simply the logical extension of this to complete

sentences: that is, thoughts are the senses of sentences. Thus for a sentence where the question of

truth or falsity arises, one understands it by grasping its thought. This qualification of the

question of truth leads to the reading that Frege understands thoughts to be almost

interchangeable with the notion of propositions. We could even read it as thoughts can only exist

for sentences that assert a proposition. (Furthermore, this rules out questions, commands, and

desires as having thoughts for there is no question of truth-value in such cases.) Essentially, the

thought of a sentence is its meaning. However, we must then ask how one can move from the

sense of individual linguistic expressions to the thought of the whole sentence. Here, Frege sets a

precedent still adhered to by contemporary linguistics and semanticians today: the

compositionality of meaning. That is, a sentence’s meaning is constructed from the meaning of

its individual parts and the syntactic structure those parts assume.

Finally, Frege’s argument comes full circle, returning to the notion of what truth is. Frege

argues that, just as the sense has a referent of, say, some physical object in the world, a thought

refers to a truth-value. Thus when one utters a sentence containing a thought (that is, there is a

proposition for which the question of truth arises) that sentence refers to either The True or The

False. In understanding that the referent of a sentence is its truth-value there is light shed on a

number of other issues at hand. First, it becomes clear that thoughts cannot be the same as ideas.

When one has an idea, the thing that brings such an idea into existence is a sense-impression;

therefore, an idea, such as green exists only in one’s own consciousness. Thoughts, however, are

distinct from ideas in that they need no bearer, existing outside of any single consciousness. This

provides for the fact that two people can obtain the same thought independently (think of

Newton and Leibniz discovering the calculus independently of one another): thoughts are true or

false in regards to the world, without any reliance on a subject to think or utter them. Opposition

to the notion that thoughts are mind-independent would lead to the inability of humans to work

on, as Frege states, a “science common to many” (43). If we take this to be the case then it

follows that different sentences can express the same thought. Moreover, Frege’s account helps

us deal with cases involving non-existents. Taking the classic example, ‘The present king of

France is wise,’ we see that the individual terms all have a sense; but the subject of the sentence

has no reference. Thus we can grasp the meaning of the sentence for we understand the senses

associated with the expressions but the sentence can be neither true nor false because there is no

thought associated to the sentence that refers to a truth-value.