Some Ruby methods accept optional boolean arguments. This kind of os parameter is known to be confusing since you cannot tell just looking at the method call what the parameter mean. For example: ```ruby object.respond_to?(:symbol, false) # what does `false` mean? object.methods(true) # what does `true` mean? ``` Now compare that to ```ruby object.respond_to?(:symbol, include_all: false) # what does `false` mean? object.methods(regular: true) # or object.methods(only_public: true) # or object.methods(include_all: false) ``` I know Matz doesn't like a breaking changes, so maybe we could have both to not break current calls, but allow a nicer syntax in newer Ruby? I don't know the depths of the Ruby C implementation, so here's what I thought in plain Ruby: ```ruby def respond_to?(symbol, include_all_positional=false, include_all: nil) include_all ||= false # ... end ``` I'm willing to tackle this, if approved.