Using reason without applying it to experience only leads to theoretical illusions. Ideas derived from real world experiences lead to acquisition of knowledge, and the accumulation of time-tested principles leads to wisdom.

Meaning: Advice offered after an irreversible action cannot prevent what has already happened. Give relevant guidance while someone can still use it, and distinguish prevention from help with what comes next.

Meaning: The saying treats April and May as decisive months for what the rest of the year will yield. Keys picture their conditions as opening or closing later possibilities.

Meaning: The rhyme presents a spring ague as medicine fit for a king. It gives a feverish illness a surprising positive value rather than simply treating it as misfortune.

Meaning: April’s wind is pictured as a horn announcing favourable conditions for hay and corn. The saying links an early-season sign with a hoped-for later yield.