Confusion with how thenable callback works in Promise?

I am new to JS and was learning promises. The code excerpt I want to show is this

promisedFunction.then(data=>console.log(data))

or simply

promisedFunction.then(console.log)

which is equivalent of the former code excerpt. The question is how is that possible to just use then(console.log) instead of then(data=>console.log(data))? Does it mean that we can omit the passed-from-promise data in thenable callback?