APAD: Every why has a wherefore.

Every why has a wherefore.

Everything has a reason or explanation behind it. We should seek to understand the causes and reasons behind things, rather than simply accepting them at face value. Every question or reason (why) has a corresponding explanation or purpose (wherefore). It emphasizes that there's always a cause or reason behind an action, decision, or situation.

"Why": generally refers to the question of reason or cause. 

"Wherefore": historically meant "for what reason" or "why," and is often used in older texts to mean the same thing. In modern English, it's not commonly used, but it emphasizes the underlying cause or explanation. 
The phrase, "the whys and wherefores," is used to refer to the complete reasons or explanations for something.

Therefore, "Every why has a wherefore" is a way of saying that every question has an answer, or every effect has a cause. It highlights the idea that things don't happen randomly, but are driven by underlying reasons or motivations.

Every why hath a wherefore.

From William Shakespeare: Comedy of Errors, Act II, Scene II

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Antipholus of Syracuse

Shall I tell you why?

Dromio of Syracuse

Ay, sir, and wherefore; for they say every why hath a wherefore.

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