Two doors—red and blue—represent philosophical doubt in behavior analysis: questioning assumptions and staying open to evidence.

Philosophical Doubt: The Art of Asking “What If I’m Wrong?”

We’ve covered Selectionism, Determinism, Parsimony, and Pragmatism. Now it’s time for another cornerstone of good science—Philosophical Doubt.

This isn’t a TCO-listed term, but it’s a big part of how our field keeps growing. It’s the attitude that says:

“Even if I feel sure, I should keep questioning.”

It’s not about second-guessing everything forever. It’s about leaving the door open for new evidence, new perspectives, and better solutions.

Everyday Philosophical Doubt

Picture this: You swear your phone charger stopped working because your toddler bent the cord.
Then a week later, you realize the outlet itself was faulty.

Or maybe you’ve always believed your neighbor waters their lawn at 6 a.m. every day… until you see the sprinkler timer set for 5 p.m.

Philosophical doubt is what keeps you from locking in too early on your first explanation.

The Roommate Who Hates Dish Duty (or Does She?)

Let’s borrow a familiar setting. You come home to a mountain of dirty dishes in the sink. You think:

Locked-in assumption: “Becky is lazy.”
A more careful stance: “It seems like Becky didn’t do the dishes. But I should check—maybe the dishwasher’s broken, maybe she’s been out all day, maybe she thought they were clean.”

Philosophical doubt reminds you that your first take might not be the whole picture.

Clinical Example: When “Attention” Wasn’t the Function

You run a functional analysis. At first glance, the data looks like clear attention-maintained behavior. You could stop there and build an intervention.

But something feels off. The student’s behavior also happens during downtime when no demands are placed—and you’re not delivering attention.

A little more digging reveals that the real maintaining variable was access to preferred sensory items they were more likely to get after a disruption.

If you hadn’t questioned your first interpretation, you’d have built an intervention that didn’t match the function.

Supervising Staff: The “This Always Works” Trap

You’ve got a behavior plan you’ve used successfully with multiple students. A new teacher says, “This one’s different.”

It’s tempting to think, “Nope, I’ve got the data, I know it works.”

Philosophical doubt says, “Maybe this student’s context changes how the plan works. Let’s watch closely, take more data, and adjust if needed.”

Why It Matters in ABA

In our field, Philosophical Doubt helps us:

Avoid the one-size-fits-all problem
Catch when our explanations are built on incomplete data
Stay flexible as new information comes in
Build credibility by showing we’re open to change when the evidence points us there

How to Practice Philosophical Doubt

Check your data twice: Ask yourself if other variables could explain what you’re seeing.
Actively seek disconfirming evidence: Look for situations where your current explanation doesn’t fit.
Invite feedback: A colleague’s fresh eyes might spot something you’ve normalized.
Remember your sample size: One success doesn’t mean universal application.

The Takeaway

Philosophical doubt doesn’t make you indecisive—it makes you better.
It’s the difference between charging ahead with a “good enough” guess and building solutions that actually fit reality.

In ABA, where the stakes are people’s lives, learning, and independence, it’s worth taking that extra moment to ask:

“What am I missing?”

Happy studying,

The Learning Behavior Analysis Team