A new easy theorem in my draft. Theorem $latex \mathrm{DOM} (g \circ f) \supseteq \mathrm{DOM} f$, $latex \mathrm{IM} (g \circ f) \supseteq \mathrm{IM} g$, $latex \mathrm{Dom} (g \circ f) \supseteq \mathrm{Dom} f$, $latex \mathrm{Im} (g \circ f) \supseteq \mathrm{Im} g$ for every…

read moreThis is a very short addition to my book, in response to a person who criticized my style. He may be partly right, but: The proofs are generally hard to follow and unpleasant to read as they are just a bunch of…

read moreI have rewritten the section “More results on restricted identities” of this draft. Now it contains some new (easy but important) formulas.

read moreI have developed my little addition to category theory, definition and research of properties of unfixed morphisms. Unfixed morphisms is a tool for turning a category (with certain extra structure) into a semigroup, that is abstracting away objects. Currently this research is…

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