Learn Spanish (Latin America): Capaz que sea una simple coincidencia.

The phrase capaz que expresses doubt, possibility, or a guess—very similar to tal vez or quizás. When you want to emphasize the uncertainty of your guess ("it might be"), you use the subjunctive.

Could I use the indicative es instead of sea?

Yes, you can! In many parts of Latin America, capaz que is frequently used with the indicative. Saying Capaz que es una simple coincidencia is perfectly natural. Using the indicative makes it sound a bit more like a confident statement or a strong suspicion ("Maybe it is..."), while the subjunctive keeps it feeling more hypothetical.

I learned that capaz means "capable". How does it mean "might" or "maybe" here?

While ser capaz de does mean "to be capable of," the fixed phrase capaz que (or sometimes just capaz) is a very common conversational shortcut in Latin America. It translates best as "maybe" or "it's possible that." You can loosely think of it as a shortened version of "It is capable of being true that..."

Why is simple placed before coincidencia?