7/30/26
The intellectual backdrop here is Steven A. Stegeman's book The Return of Rationality: A Closed System of Propositional Logic: Stegeman, Steven A.: 9798993350851: Amazon.com: Books
There will be the need to write logical symbols. Here are the ones in use.
'not' : ∼ (the 'tilde'), ¬ (looks like the top right corner of a box)
'and': ∙ (bullet operator) . (just a period), &, ∧
'or': ∨ (vel)
'exclusive or': ⊕
'implication': ⊃, →
'equivalence': ≡, ↔
'therefore': ∴
The Stegeman book primarily uses ~, ∙, v, ⊕, ⊃, and ≡. A palette will be provided for typing these.
[There is a little trick/elegance that the SoftOption software uses. In a logic book, you might see (A&B)→C and that is just the same logically as the formula (A∧B)⊃C but in different symbols. The software will try to make sense of what you write to the extent that if you use the 'wrong' symbol for, say, negation (ie a symbol for negation but not the one your system uses) the software will read it and understand— and when the software writes to you it will use your symbols. In a sense that is, garbage in garbage not out.]
These logical symbols do have html codes:
'not' : ∼ (the 'tilde'), ¬ (looks like the top right corner of a box)
'and': ∧,& (the ampersand), . (just a period)
'bullet and': &8729;
'or': ∨
'exclusive or': ⊻
'implication': ⊃ , →
'equivalence': ≡ , ↔
'therefore': ∴
So, for example, you insert into the html of a web page '∴' you will get ∴
Wikipedia has a table of logical symbols
Introductory Video
[The narrator mis-speaks at one point saying 'hook' for 'or'.]