basic idea

basic thought central principle central thought main idea main point

core crux essence gist heart keynote pith point substance

basic principle basis

basis center core cornerstone criterion crux essence gist heart idea kernel keystone linchpin mainspring marrow measure motive nub pith principle root source spring standard substance

central idea

end exterior exteriority outside periphery result surface

basis center core cornerstone criterion crux gist heart idea kernel linchpin mainspring marrow measure motive nub pith principle root source spring standard substance