包含関係

word(cc,p) … \(\subset\)  \(\subsetneq\)  
def …【\({\sf X} \subset {\sf Y}\)】≃【\(\forall {\sf x} \in {\sf X} . {\sf x} \in {\sf Y}\)
def …【\({\sf X} \subsetneq {\sf Y}\)】≃【\({\sf X} \subset {\sf Y} , {\sf X} \neq {\sf Y}\)
word(ss,p) … \(\subset\)  \(\subsetneq\)  
\({\subset.}\)\(X \subset Y \Longleftrightarrow X \subset Y\)
\({\subsetneq}.\)\(X \subsetneq Y \Longleftrightarrow X \subsetneq Y\)
\({=}{.}{.}\)\(X = Y \Longleftrightarrow X \subset Y \subset X\)\(\,{\blacktriangleleft}\,\mathbb{D}.\)

2項述語に対する1項述語

abbr …【\(\mathop{{\sf p}} \cdots \text{自}\)】≈【\(\forall {\sf x} \, ( {\sf x} \mathop{{\sf p}} {\sf x} )\)
abbr …【\(\mathop{{\sf p}} \cdots \text{推}\)】≈【\(\forall {\sf x} , {\sf y} , {\sf z} \, ( {\sf x} \mathop{{\sf p}} {\sf y} \mathop{{\sf p}} {\sf z} \Longrightarrow {\sf x} \mathop{{\sf p}} {\sf z} )\)
次のようなabbrは自動で準備されます。
abbr …【\(\mathop{{\sf p}} \cdots \text{自推}\)】≈【\(\mathop{{\sf p}} \cdots \text{自} , \mathop{{\sf p}} \cdots \text{推}\)

\({=}自推\)\(= \cdots \text{自推}\)\(\,{\blacktriangleleft}\,\text{O}\)
\({\subset}自推\)\(\subset \cdots \text{自推}\)\(\,{\blacktriangleleft}\,\mathbb{D}.\)
\({\subsetneq}推\)\(( X \subsetneq Y \subset Z ) \mathbin{\rm o\!r} ( X \subset Y \subsetneq Z ) \Longrightarrow X \subsetneq Z\)\(\,{\blacktriangleleft}\,\mathbb{D}.\)

集合の全体、空集合

word(,c) … \(\text{Set}\)  
def …【\(\text{Set}\)】≃【\(\{ x \mid \top \} \)
\(\text{Set0}\)\(x \in \text{Set}\)\(\,{\blacktriangleleft}\,\text{O}\)
\(\text{Set1}\)\(X \subset \text{Set}\)\(\,{\blacktriangleleft}\,\text{O}\)

word(,s) … \(\emptyset\)  
\({\emptyset.}\)\(\emptyset = \{ x \mid {\perp} \} \)
\(\emptyset0\)\(x \notin \emptyset\)\(\,{\blacktriangleleft}\,\mathbb{D}.\)
\(\emptyset1\)\(\emptyset \subset X\)\(\,{\blacktriangleleft}\,\mathbb{D}.\)
\(\emptyset{.}{.}\)\(x = \emptyset \Longleftrightarrow \not\exists y \, ( y \in x )\)\(\,{\blacktriangleleft}\,\mathbb{D}.\)

有限集合の生成(外延記法)

word(s\(^{\tt n}\),s)! …【\(\{ {\sf X}_{1} , \cdots , {\sf X}_{\tt n} \}\)
\(\text{set}_{\tt n}.\)\(\{ X_{1} , \cdots , X_{\tt n} \} = \{ x \mid x = X_{1} \mathbin{\rm o\!r} \cdots \mathbin{\rm o\!r} x = X_{\tt n} \} \)
例えば【\(\{ x , \{ x , y \} \}\)】はSetで、現れる2つのsetはword(ss,s)です。

合併、共通部分、差

word(cc,c) … \(\cup\)  \(\cap\)  \(\mathop\setminus\)  
def …【\({\sf X} \cup {\sf Y}\)】≃【\(\{ {\sf x} \mid {\sf x} \in {\sf X} \mathbin{\rm o\!r} {\sf x} \in {\sf Y} \} \)
def …【\({\sf X} \cap {\sf Y}\)】≃【\(\{ {\sf x} \mid {\sf x} \in {\sf X} , {\sf x} \in {\sf Y} \} \)
def …【\({\sf X} \mathop\setminus {\sf Y}\)】≃【\(\{ {\sf x} \mid {\sf x} \in {\sf X} , {\sf x} \notin {\sf Y} \} \)

word(ss,s) … \(\cup\)  \(\cap\)  \(\mathop\setminus\)  
\(\cup.\)\(X \cup Y = X \cup Y\)
\(\cap.\)\(X \cap Y = X \cap Y\)
\(\setminus.\)\(X \mathop\setminus Y = X \mathop\setminus Y\)
\({\subset}\text{u}\)\(X \subset Y \Longleftrightarrow X \cup Y = Y\)\(\,{\blacktriangleleft}\,\mathbb{D}.\)
\({\subset}\text{a}\)\(X \subset Y \Longleftrightarrow X \cap Y = X\)\(\,{\blacktriangleleft}\,\mathbb{D}.\)

2項関数に対する1項述語

abbr …【\(\mathop{{\sf f}} \cdots \text{換}\)】≈【\(\forall {\sf x} , {\sf y} \, ( {\sf x} \mathop{{\sf f}} {\sf y} = {\sf y} \mathop{{\sf f}} {\sf x} )\)
abbr …【\(\mathop{{\sf f}} \cdots \text{結}\)】≈【\(\forall {\sf x} , {\sf y} , {\sf z} \, ( {\sf x} \mathop{{\sf f}} ( {\sf y} \mathop{{\sf f}} {\sf z} ) = ( {\sf x} \mathop{{\sf f}} {\sf y} ) \mathop{{\sf f}} {\sf z} )\)
abbr …【\(\mathop{{\sf f}} \cdots \text{巾}\)】≈【\(\forall {\sf x} \, ( {\sf x} \mathop{{\sf f}} {\sf x} = {\sf x} )\)
\({\cup}換結巾\)\(\cup \cdots \text{換結巾}\)\(\,{\blacktriangleleft}\,\mathbb{D}.\)
\({\cap}換結巾\)\(\cap \cdots \text{換結巾}\)\(\,{\blacktriangleleft}\,\mathbb{D}.\)

abbr …【\(\mathop{{\sf f}} , {\sf E} \cdots \text{単}\)】≈【\(\forall {\sf x} ( {\sf x} \mathop{{\sf f}} {\sf E} = {\sf x} = {\sf E} \mathop{{\sf f}} {\sf x} )\)
\({\cup}単\)\(\cup , \emptyset \cdots \text{単}\)\(\,{\blacktriangleleft}\,\mathbb{D}.\)

abbr …【\(\mathop{{\sf f}} \cdots \text{換} \, {\sf A}\)】≈【\(\forall {\sf x} , {\sf y} {\sf A} . ( {\sf x} \mathop{{\sf f}} {\sf y} = {\sf y} \mathop{{\sf f}} {\sf x} )\)
abbr …【\(\mathop{{\sf f}} \cdots \text{結} \, {\sf A}\)】≈【\(\forall {\sf x} , {\sf y} , {\sf z} {\sf A} . ( {\sf x} \mathop{{\sf f}} ( {\sf y} \mathop{{\sf f}} {\sf z} ) = ( {\sf x} \mathop{{\sf f}} {\sf y} ) \mathop{{\sf f}} {\sf z} )\)
次のようなabbrも自動で準備されます。
abbr …【\(\mathop{{\sf f}} \cdots \text{換結} \, {\sf A}\)】≈【\(\mathop{{\sf f}} \cdots \text{換} \, {\sf A} , \mathop{{\sf f}} \cdots \text{結} \, {\sf A}\)