# What is the logical function of “and/or”?

In natural language, we often use an enumeration or list of things with only a single logical operator. I am especially puzzled by the use of "and/or" and what it is supposed to mean in this context.

I feel like it must mean the following:

IF A, B, C and/or D

(A, B, C, and D) and (A, B, C, or D)

And I feel like it must not mean each of them individually and all of their combinations ((A), (B), (C), (D), (AB), (AC), (AD), (BB), (BC), (BD), (CD), (DD), (ABC), (ABD), (BCD), or (ABCD)).

Am I correct? If not why, and how to express all the combination of an array or set in natural language?

• Please, if you downvote, help me understand your reasons. Thank you! Commented Oct 20, 2021 at 8:46

## 1 Answer

And/or is just a way to express non-exclusive or, because or is very often used as exclusive or in natural language.

I would parse "A, B, C and/or D" as "(A AND B AND C) OR D". Alternatively, if it is supposed to mean "A and/or B and/or C and/or D" then it just means "A OR B OR C OR D".

• After submitting and thinking about for a good hour in the hot tube (lol) I actually reached to your latter conclusion: In natural language, “or” is predominantly inclusive and “and” is predominantly conjunctive and when not, it functions as inclusive or depending on context. Commented Oct 20, 2021 at 8:22
• For example: You can buy bananas, apples, plums and strawberries from the neighbor lady. (The context clearly indicated you don’t have to buy from each to buy one, and will function as an inclusive “or” which does involve all the combinations — in fact, all the permutations and variations too. Commented Oct 20, 2021 at 8:25
• So if it means, A or B or C or D, what it really means is A, B, C or D. You can buy candies, fruits or plums (“or” is probably preferred over such a inclusively disjunctive “or” because it presumed you would chose alll, and therefor it conveys more truth. Commented Oct 20, 2021 at 8:28
• Thank you for your answer and reassuring! Commented Oct 20, 2021 at 8:28