Thinking is most mysterious, and by far the greatest light upon it that we have is thrown by the study of language. This study shows that the forms of a person's thoughts are controlled by inexorable laws of pattern of which he is unconscious. These patterns are the unperceived intricate systematizations of his own language--shown readily enough by a candid comparison and contrast with other languages, especially those of a different linguistic family. His thinking itself is in a language—in English, in Sanskrit, in Chinese. And every language is a vast pattern-system, different from others, in which are culturally ordained the forms and categories by which the personality not only communicates, but also analyzes nature, notices or neglects types of relationship and phenomena, channels his reasoning, and builds the house of his consciousness.

Psychologically our thought-apart from its expression in words-is only a shapeless and indistinct mass. Philosophers and linguists have always agreed in recognizing that without the help of signs we would be unable to make a clear-cut, consistent distinction between two ideas. Without language, thought is a vague, uncharted nebula. here are no pre-existing ideas, and nothing is distinct before the appearance of language.

Language is the picture and counterpart of thought.

We are thus able to distinguish thinking as the function which is to a large extent linguistic.

Thinking is language spoken to oneself. Until language has made sense of an experience, that experience is meaningless.

The characteristic role of language with respect to thought is not to create a material phonic means for expressing ideas but to serve as a link between thought and sound, under conditions that of necessity bring about the reciprocal delimitations of units. Thought, chaotic by nature, has to become ordered in the process of its decomposition. Neither are thoughts given material form nor are sounds transformed into mental entities; the somewhat mysterious fact is rather that "thought-sound" implies division, and that language works out its units while taking shape between two shapeless masses. Visualize the air in contact with a sheet of water; if the atmospheric pressure changes, the surface of the water will be broken up into a series of divisions, waves; the waves resemble the union or coupling of thought with phonic substance.

Thought is prior to language and consists in the simultaneous presentation to the mind of two different images.

In the late 1930s a Polish count, Alfred Korzybski, pointed out yet another aspect of consciousness — language. Language molds thought, he said, laying out the principles of General Semantics. We confuse it with reality; it creates false certainties. With words we try to isolate things that can only exist in continuity. We fail to see process, change, movement. If we are to experience reality, Korzybski and his followers said, we must acknowledge the limits of language.

The relation between language and thought are discussed in Stuart Chase, Power of words (1954), especially Chapter 10; the important sourcebooks in this area are Alfred Korzybski, Science and Sanity: An Introduction to Non-Aristotelian Systems and General Semantics, 4th ed. (1958), and John B. Carroll, ed., Language, Thought, and Reality: Selected Writings of Benjamin Lee Whorf (1956).

I would say with regard to critical thought, and to some degree with regard to productive thought, an indeterminate proportion of that is dependent on speech. I don't think it's unreasonable to point out that thought is internalized speech. And that the dialectical process that constitutes critical thinking is internalized speech. […] The quality of our thoughts is actually dependent on our ability to speak our minds.

Experiments... have shown that at least one aspect of human thought—memory—is strongly influenced by language.

Language is the dress of thought.

It is clear that all verbal structures with meaning are verbal imitations of that elusive psychological and physiological process known as thought, a process stumbling through emotional entanglements, sudden irrational convictions, involuntary gleams of insight, rationalized prejudices, and blocks of panic and inertia, finally to reach a completely incommunicable intuition.

The materialist theory of knowledge amounts, then, to this statement, that the human organ of cognition radiates no metaphysical light, but is a piece of Nature which pictures other pieces of Nature whose essence is explained when we describe it and bring it in connection with the whole Universe as the one Reality and the real Unity. Such a description demands from the epistemologist or philosopher that he should treat his subject in the same precise way as the animal world is treated by the zoologist. Should I be reproached with not following this precept immediately, I would point to Rome which, too, was not built in one day.