Thoughts, beliefs, attitudes, and opinions are a group of common threads that bind us. To take into one's mind is a continuous activity.
Something conceived in the mind can be called "concepts".
"Theories" are the general principle or body of principles that are put together to try and explain phenomena that we take into the mind. These theories form a belief, policy, or procedure proposed or followed as the basis of action.
From the theories, "principles" are form as a matter or thing of primary importance. These principals become the most consequential or influential items directing the beliefs and opinions we form in the mind.
"Methods" are derived from these principles that produce an orderly or habitual way for doing something. They may be techniques, or processes that give an orderliness and regularity to our lives.
"Tools" then are formed, and become a means to an end. The manner of conducting oneself is a result.
Concepts...to theories...to principles...to methods... and to tools, form a framework our thoughts utilize. Common threads we all share.