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1. • CommentRowNumber1.
   • CommentAuthorUrs
   • CommentTimeJul 3rd 2018
   • PermaLink
   Author: Urs
   Format: MarkdownItexa table of logical symbols, to be !included in the relevant entries under "related concepts" <a href="https://ncatlab.org/nlab/revision/logic+symbols+--+table/1">v1</a>, <a href="https://ncatlab.org/nlab/show/logic+symbols+--+table">current</a>

   a table of logical symbols, to be !included in the relevant entries under “related concepts”

   v1, current

2. • CommentRowNumber2.
   • CommentAuthorIngoBlechschmidt
   • CommentTimeJul 3rd 2018
   • PermaLink
   Author: IngoBlechschmidt
   Format: MarkdownItexRemarked that "$\neq$" can also mean "apartness". I don't mind removing this entry again, if we decide that the wider table doesn't look good. <a href="https://ncatlab.org/nlab/revision/diff/logic+symbols+--+table/3">diff</a>, <a href="https://ncatlab.org/nlab/revision/logic+symbols+--+table/3">v3</a>, <a href="https://ncatlab.org/nlab/show/logic+symbols+--+table">current</a>

   Remarked that “$\neq$” can also mean “apartness”. I don’t mind removing this entry again, if we decide that the wider table doesn’t look good.

   diff, v3, current

3. • CommentRowNumber3.
   • CommentAuthorUrs
   • CommentTimeJul 3rd 2018
   • (edited Jul 3rd 2018)
   • PermaLink
   Author: Urs
   Format: MarkdownItexThanks, good point. How about just using a slash, as in some of the other entries: *** | $\phantom{A}$symbol$\phantom{A}$ | $\phantom{A}$meaning$\phantom{A}$ | |--------|---------| | $\phantom{A}$$\in$ | $\phantom{A}$[[element]] [[relation]] | | $\phantom{A}$$\,:$ | $\phantom{A}$[[type|typing]] [[relation]] | | $\phantom{A}$$=$ | $\phantom{A}$[[equality]] | | $\phantom{A}$$\vdash$$\phantom{A}$ | $\phantom{A}$[[entailment]] / [[sequent]]$\phantom{A}$ | | $\phantom{A}$$\top$$\phantom{A}$ | $\phantom{A}$[[true]] / [[top]]$\phantom{A}$ | | $\phantom{A}$$\bot$$\phantom{A}$ | $\phantom{A}$[[false]] / [[bottom]]$\phantom{A}$ | | $\phantom{A}$$\Rightarrow$ | $\phantom{A}$[[implication]] | | $\phantom{A}$$\Leftrightarrow$ | $\phantom{A}$[[logical equivalence]] | | $\phantom{A}$$\not$ | $\phantom{A}$[[negation]] | | $\phantom{A}$$\neq$ | $\phantom{A}$[[negation]] of [[equality]] / [[apartness]]$\phantom{A}$ | | $\phantom{A}$$\notin$ | $\phantom{A}$[[negation]] of [[element]] [[relation]] $\phantom{A}$ | | $\phantom{A}$$\exists$ | $\phantom{A}$[[existential quantification]]$\phantom{A}$ | | $\phantom{A}$$\forall$ | $\phantom{A}$[[universal quantification]]$\phantom{A}$ | | $\phantom{A}$$\wedge$ | $\phantom{A}$[[logical conjunction]] | | $\phantom{A}$$\vee$ | $\phantom{A}$[[logical disjunction]] | | $\phantom{A}$$\otimes$$\phantom{A}$ | $\phantom{A}$[[multiplicative conjunction]]$\phantom{A}$ | | $\phantom{A}$$\oplus$$\phantom{A}$ | $\phantom{A}$[[multiplicative disjunction]]$\phantom{A}$ |

   Thanks, good point. How about just using a slash, as in some of the other entries:

   ---

   $\phantom{A}$symbol$\phantom{A}$	$\phantom{A}$meaning$\phantom{A}$
   $\phantom{A}$$\in$	$\phantom{A}$element relation
   $\phantom{A}$$\,:$	$\phantom{A}$typing relation
   $\phantom{A}$$=$	$\phantom{A}$equality
   $\phantom{A}$$\vdash$$\phantom{A}$	$\phantom{A}$entailment / sequent$\phantom{A}$
   $\phantom{A}$$\top$$\phantom{A}$	$\phantom{A}$true / top$\phantom{A}$
   $\phantom{A}$$\bot$$\phantom{A}$	$\phantom{A}$false / bottom$\phantom{A}$
   $\phantom{A}$$\Rightarrow$	$\phantom{A}$implication
   $\phantom{A}$$\Leftrightarrow$	$\phantom{A}$logical equivalence
   $\phantom{A}$$\not$	$\phantom{A}$negation
   $\phantom{A}$$\neq$	$\phantom{A}$negation of equality / apartness$\phantom{A}$
   $\phantom{A}$$\notin$	$\phantom{A}$negation of element relation $\phantom{A}$
   $\phantom{A}$$\exists$	$\phantom{A}$existential quantification$\phantom{A}$
   $\phantom{A}$$\forall$	$\phantom{A}$universal quantification$\phantom{A}$
   $\phantom{A}$$\wedge$	$\phantom{A}$logical conjunction
   $\phantom{A}$$\vee$	$\phantom{A}$logical disjunction
   $\phantom{A}$$\otimes$$\phantom{A}$	$\phantom{A}$multiplicative conjunction$\phantom{A}$
   $\phantom{A}$$\oplus$$\phantom{A}$	$\phantom{A}$multiplicative disjunction$\phantom{A}$

4. • CommentRowNumber4.
   • CommentAuthorUrs
   • CommentTimeNov 7th 2022
   • (edited Nov 7th 2022)
   • PermaLink
   Author: Urs
   Format: MarkdownItexThe second but last line of the `!include`-file *[[logic symbols -- table]]* paired "multiplicative disjunction" with the symbol "$\oplus$" This seems at best non-standard, even according to our own entry *[[multiplicative disjunction]]*. [ edit: Hm, it looks like I myself typed that in [rev 1 ](https://ncatlab.org/nlab/revision/logic+symbols+--+table/1) in 2018 ] I went ahead and * made instead "$\invamp$" appear as the symbol for multiplicative disjunction * added a line *[[additive disjunction]]* for the symbol "$\oplus$" and will start the corresponding entry now <a href="https://ncatlab.org/nlab/revision/diff/logic+symbols+--+table/5">diff</a>, <a href="https://ncatlab.org/nlab/revision/logic+symbols+--+table/5">v5</a>, <a href="https://ncatlab.org/nlab/show/logic+symbols+--+table">current</a>

   The second but last line of the !include-file logic symbols – table

   paired “multiplicative disjunction” with the symbol “$\oplus$”

   This seems at best non-standard, even according to our own entry multiplicative disjunction.

   [ edit: Hm, it looks like I myself typed that in rev 1 in 2018 ]

   I went ahead and

   • made instead “$\invamp$” appear as the symbol for multiplicative disjunction

   • added a line additive disjunction for the symbol “$\oplus$” and will start the corresponding entry now

   diff, v5, current

5. • CommentRowNumber5.
   • CommentAuthornLab edit announcer
   • CommentTimeNov 7th 2022
   • PermaLink
   Author: nLab edit announcer
   Format: MarkdownItexadded line for $\&$ for [[additive conjunction]] Anonymous <a href="https://ncatlab.org/nlab/revision/diff/logic+symbols+--+table/6">diff</a>, <a href="https://ncatlab.org/nlab/revision/logic+symbols+--+table/6">v6</a>, <a href="https://ncatlab.org/nlab/show/logic+symbols+--+table">current</a>

   added line for $\&$ for additive conjunction

   Anonymous

   diff, v6, current

6. • CommentRowNumber6.
   • CommentAuthorUrs
   • CommentTimeNov 8th 2022
   • PermaLink
   Author: Urs
   Format: MarkdownItexadded also row for *[[linear implication]]* <a href="https://ncatlab.org/nlab/revision/diff/logic+symbols+--+table/7">diff</a>, <a href="https://ncatlab.org/nlab/revision/logic+symbols+--+table/7">v7</a>, <a href="https://ncatlab.org/nlab/show/logic+symbols+--+table">current</a>

   added also row for linear implication

   diff, v7, current

7. • CommentRowNumber7.
   • CommentAuthorUrs
   • CommentTimeNov 8th 2022
   • PermaLink
   Author: Urs
   Format: MarkdownItexand one for *[[exponential conjunction]]* <a href="https://ncatlab.org/nlab/revision/diff/logic+symbols+--+table/7">diff</a>, <a href="https://ncatlab.org/nlab/revision/logic+symbols+--+table/7">v7</a>, <a href="https://ncatlab.org/nlab/show/logic+symbols+--+table">current</a>

   and one for exponential conjunction

   diff, v7, current

8. • CommentRowNumber8.
   • CommentAuthornLab edit announcer
   • CommentTimeNov 8th 2022
   • PermaLink
   Author: nLab edit announcer
   Format: MarkdownItexadded section for [[type theory]]/[[propositions as types]], moved [[function type]] over to that section, and added symbols for [[product type]], [[dependent product type]], [[sum type]], [[dependent sum type]], [[empty type]], and [[unit type]] Anonymous <a href="https://ncatlab.org/nlab/revision/diff/logic+symbols+--+table/9">diff</a>, <a href="https://ncatlab.org/nlab/revision/logic+symbols+--+table/9">v9</a>, <a href="https://ncatlab.org/nlab/show/logic+symbols+--+table">current</a>

   added section for type theory/propositions as types, moved function type over to that section, and added symbols for product type, dependent product type, sum type, dependent sum type, empty type, and unit type

   Anonymous

   diff, v9, current