EN
The present article reviews the Polish-language edition of Gottlob Frege’s scientific correspondence. In the article, I discuss the material hitherto unpublished in Polish in relation to the remainder of Frege’s works. First of all, I inquire into the role and nature of definitions. Then, I consider Frege’s recognition criteria for sameness of thoughts. In the article’s third part, I study letters devoted to the principle of semantic compositionality, while in the fourth part I discuss Frege’s remarks concerning the context principle.