logji -loj- gismu

x1 [rules/methods] is a logic for deducing/concluding/inferring/reasoning to/about x2 (du'u).

Also (adjective:) x1, x2 are logical. See also nibli.

In notes:

lojbo
x1 reflects [Loglandic]/Lojbanic language/culture/nationality/community in aspect x2.
nibli
x1 logically necessitates/entails/implies action/event/state x2 under rules/logic system x3.
lojycpa
x1 infers/concludes/draws conclusion x2 from premise x3 based on logic/reasoning x4.
lojysarxe
x1 is harmonious with logical philosophy/thought in aspect x2 (ka); x1 is logical (one sense)
lojyske
x1=s1 is the science of logic based on methodology x2=s3.
selni'i
n2 logically follows n1 under rules/logic system n3.
toldralogji
x1 [rules/methods] is a logical fallacy for deducing/concluding/inferring/reasoning to/about x2 (du'u)
didni
x1 deduces/reasons by deduction/establishes by deduction that x2 is true about x3 from general rule x4