cohesion.rb

class SomeClass
	def initialize a, b, c
		@a, @b, @c = a, b, c
	end

	def some_method
		do_something_with @a, 
		some_work_with @b
	end

	def some_other_method
		something_with @a, @b
	end

	def yet_another
		@b.act_upon @a
	end

	def odd_ball_method
		@c.something_else @a
	end
end

@b & @A are related strongly. @c, not so much.

when writing a test you'll notice that whatever mock you use for @c will be rarely considered. are that point i'd consider passing c as an argument to odd_ball_method or figuring out a different design altogether.