The Liskov Substitution Principle, A Model for Parenting

Source: Dev.to

Maybe it’s just me, but most software principles sound abstract until you realize they already exist in real life 🌱

While studying the SOLID principles, I noticed that one of the clearest examples is the Liskov Substitution Principle (LSP) — a core concept in object‑oriented design — which maps surprisingly well to parenting and family expectations 👨‍👩‍👧‍👦

🔍 What LSP Says (in simple terms)

In software, LSP states:

If a class B is a subtype of class A, objects of type A should be replaceable with objects of type B without breaking the behavior expected by the client.

In plain terms:

If you make a promise at a higher level, every specific case must be able to honor it 🤝

Now replace:

• class → child 👶
• client → family 🏠

Suddenly, the principle becomes very human.

👪 Parents, Promises, and Abstractions

• In software, a base class defines expectations.
• In a family, parents define rules and responsibilities.

Problems arise when a parent says:

“All my children must do X.”

…but not all children are actually capable of doing X.

When that happens, the child isn’t the problem. The expectation is. ⚠️

That’s exactly what happens in software when a base class defines behavior that not all subclasses can safely support.

🤥 When the Parent Is “Lying”

In programming, we say an abstraction is lying when it promises behavior that isn’t universally valid.

In families, this looks like:

• Expecting every child to succeed in the same way 🎯
• Assigning the same responsibilities regardless of age or ability 🧱
• Punishing children for expectations that never fit them 🚫

In software, the result is broken behavior.
In families, it’s frustration, resentment, and constant conflict 💥

🧠 The Shared Lesson

Whether you’re designing software or raising a family:

If someone constantly has to say “I can’t do that,” the promise was probably wrong.

LSP teaches developers to look upward, not downward — to fix the contract instead of blaming the implementation 🔄

🌟 Final Thought

Strong systems — technical or human — are built on clear expectations, honest promises, and respect for differences.

• When abstractions are truthful, substitution becomes safe.
• When expectations are fair, relationships become healthy 💚