Knowledge has an intentionality that enables concepts, statements, and arguments to function as logical tools for getting knowledge of something.
The most basic feature of all knowledge and awareness is that it's always about something other than itself. It refers to something other than itself. We have an experience of beauty, a feeling of pain, a concept of a triangle. We make statements about gravitational objects, and arguments that are about the interior angles of a triangle equaling two right angles. All awareness, all consciousness, all knowledge, is about something other than itself. It tends into, or intends, something distinct from itself. Intentionality is one of the most basic traits of knowledge. All knowledge is intentional and every item of knowledge is an intention.
The moment we start to think about it, we can see the same of/about structure contained in instances of knowledge in all acts of will. I intend to study, the purposing of something, and so on. Willing and purposing are intentional because they contain a cognitively intentional element. I can find out the purpose of being courteous only when I have knowledge of what courtesy is.
So knowledge is intentional: it's always of or about something other than itself. It points or refers to something other than itself. This distinguishes instances of knowledge from other things. My concept of a triangle or my statement about its interior angles is of the triangle or about the triangle. But the triangle isn't of or about anything. It's just itself. So intentionality is the unique and most basic general characteristic of all items of consciousness.
That being so, the tools used to get knowledge are also intentional. Knowledge tools, like knowing itself, are necessarily revealing, disclosing, and meaningful. The tools we use to know reality must be signs of reality. So all cognitive tools are signs. An understanding and use of logic requires some knowledge of signs.