Most people may, indeed almost certainly will, at times think in the realm of universal concepts - for example, this is the spontaneous thinking of childhood.
After all, at first we only have real true universal concepts to think-with - because they are 'built-in' in the sense that we are born able to access them (albeit very partially at first). However the spontaneous thought of childhood (or of, apparently, some hunter gatherer and tribal societies) is a passive thinking - by which I mean that the thinking is a product of prior causes.
By 'passive' I mean not-creative; we think what we do, because of what - in our environment, experience, memories etc - has triggered thoughts: this type of thinking is an effect not a cause. Childhood thinking is not free; but a constrained and channeled product.
If the passive thinking is using real true universal concepts, then it is true; but it is not free. It is not 'our' thinking, it does not change the web of causes and effects in the world. Such a thinker is in the (real true) world, participating in the world; but does not change the world - rather is changed by it.
However, most modern people, most of the time, do not in their thinking participate in the real, true and universal world of concepts; instead they think by using what might be termed communicated-concepts.
Communicated concepts are not a part of the realm of real, true universal concepts - they come from communications - from the people around us, from schools and colleges, from government propaganda and (mostly, nowadays) from the mass media.
Communicated concpets may also be devised by ourselves - in what appears (superficially) to be an act of creativity, but it is actually merely 'novelty'; is actually merely a selection, combination or extrapolation of other communicated concepts.
Communicated concepts are therefore percepts, inputs - and they are only possible because of the already-existing world of real true concepts that serve as an interpretative background and provide that which makes communicated concepts 'work'.
However, the communicated concepts may (usually do) make-up a surface world of thinking, a 'fake personality', which may come to occupy all attention and block our ability to think with real true concepts - indeed, that has been precisely the history of modern thought as it developed over the past several centuries.
Because communicated concepts are an artificial thought world, they can be shaped to serve immediate human wishes, to achieve human will - sometimes useful, sometime harmfully - but never in a way which engages with with the real true world.
So communicated concepts are the cause of the modern malaise of alienation - the sense (and reality) of our thinking being cut-off from reality, from each other - and from our-selves.
In thinking with communicated concepts, modern grown-up man has detached himself from the web of cause and effect, he is no longer a passive responder only - and is in that sense Modern Man is free.
Modern Man is Free but he is disengaged from reality; free but only among artificialities and pragmatic notions.
Free; but cut-off from the truth of universal concepts.
Pure Conceptual Thinking is active, creative
Pure Conceptual Thinking is therefore a thinking with real, true and universal concepts - but it is a free, active and purposive thinking in this realm of universal concepts - and in that vital respect differs from the thinking of childhood.
The difference can be summarised by the concept of creativity. A young child thinks with real true concepts (albeit in a partial, selective and therefore distorted fashion) and therefore spontaneously lives in the realm of reality - but passively because immersed in the web of cause and effect. The typical modern adult thinks with artificial, arbitrary and merely-expedient (although often very 'useful') communicated concepts - but is free, because detached from the web of causation.
Pure Conceptual Thinking is like spontaneous childhood thinking, in that it is in the realm of universal concepts - therefore intrinsically dealing with truth and reality, and naturally engaged with the primary stuff of reality - overcoming of alienation.
But Pure Conceptual Thinking is free - in the sense that the thinking is not passively caused; the self is detached from the web of causes and effects, stands apart and both observes the flow of concepts in the thinking of universal reality and also (from its status as free, as an agent, as capable of uncaused thoughts) may contribute one or more new concepts to Mankind's sock of universal concepts.
This is primary creativity: which is to contribute to the universally-available stock of real true concepts with which Man may think.
Primary creativity happens (or may happen) during Pure Conceptual Thinking - and it happens in full and purposive awareness of what is happening - in awareness of the web of existing universal concepts, and in awareness of our own originating of a new concept added to that stock.
Such new universal concepts are available to all Men (capable of thinking them) without any need for communication; although those who subsequently use these new concepts do not necessarily realise that they are new, now do users of the new thought typically know anything of its origin.
Unless a primary creative thought has been communicated 'by the normal channel's (e.g. by speaking, reading and other media) - and all such channels use merely communicated concepts, hence are prone to falsehood, distortion and even inversion - the user the user of a new universal concept does not know who first thought it; does not know who created it; nor where or when this happened.
Typically only the one who first made this new universal concept, when engaged in Pure Conceptual Thinking and acting freely as an agent among the web of universal concepts, will know for sure what has been done.
But to contribute to Mankind's stock of universal concepts is, surely, the primary act of purposive creativity in this mortal life.