Define "environment" in the context of truth tables

Question

I'm looking at this site of MIT Open Courseware: https://ocw.mit.edu/courses/electrical-engineering-and-computer-science/6-042j-mathematics-for-computer-science-spring-2015/proofs/tp2-2/truth-tables-video/

I'm trying to understand the meaning of "environment" in the context of a truth table. Based on the site, I understand that an "environment" is something that determines if a proposition is True of False (the video states this at 50 seconds).

However, at 4:15 (in the video. 4 minutes and 15 seconds), the professor states that an environment is also the row of a truth table?

Correct me if my understanding of the video is wrong but is an "environment" both that?

Answer 1

Yes, it is both. A row on a truth table is the information about the logical value of the input propositions and the output proposition. An environment is just specific values for the propositions.

Just for fun: the NOR(NOT OR) operator can construct every possible logical operator, such as AND, NOT, XOR, IF-THEN, etc.

Answer 2

You can think of an 'environment' as a 'situation' or 'scenario' or 'possible state of affairs' ... which is exactly what rows in a truth-table represent