The true direction of the development of thinking is not from the individual to the social, but from the social to the individual.

It is through others that we become ourselves.

Thought is not merely expressed in words, it comes into existence through them

It may be said that the basic characteristic of human behavior in general is that humans personally influence their relations with the environment and through that environment personally change their behavior, subjugating it to their control.

Experience teaches us that thought does not express itself in words, but rather realizes itself in them

Every function in the child's cultural development appears twice: first, on the social level, and later, on the individual level; first, between people (interpsychological) and then inside the child (intrapsychological). This applies equally to voluntary attention, to logical memory, and to the formation of concepts. All the higher functions originate as actual relationships between individuals.

There is reason to believe that voluntary activity, more than highly developed intellect, distinguishes humans from the animals which stand closest to them.