You Absolutely CAN Prove A Negative

A common phrase that pops up among philosophy noobs is: “You can’t prove a negative.”
But this is simply not true.

Here are some clear examples of different kinds of negative statements that can be proven:

• Conceptual truths: “There are no married bachelors.” This is a negative statement, and it can be proven by definition.

• Mathematical truths: “There is no greatest prime number.” This is a negative statement, and it has a rigorous proof.

• Scientific truths: “Vaccines don’t cause autism.” This is a negative causal claim that has been tested and demonstrated.

• Everyday empirical truths: “There is no spaghetti monster in my kitchen.” This is a negative claim you can verify by looking.

• Historical truths: “There were no Roman jet planes in the 3rd century.” This is a negative claim supported by historical evidence.

• Legal truths: “There is no law in the U.S. Constitution that gives the president the power to dissolve Congress.” Negative, but provable by reading the text.

• Geographical truths: “There is no mountain on Earth taller than Mount Everest.” Negative but provable by measurement.

And so on, and so on.

Ironically, if one could prove that “you can’t prove a negative,” that itself would be proving a negative, which collapses the slogan into self-contradiction.