Thoughts which happen without effort are more often authentic, deeper and closer to my life than the results of careful step by step reasoning. Maybe this is because they reflect not only the world, but also how I relate to it.
In fact, understanding jumps and logic follows .
Living thought - the one able to embrace complexity and also to make our own sense from it - appears to us as effortless common sense, not belaboured reasoning.
I hurl a concern through the unconscious rich abyss of my mind and it comes back dripping with the honey of everything I ever forgot.
I see, grasp a shape, a family resemblance, a meaning and suddenly I understand.
I throw a glance to an obstacle and the way around it shows in a blink, if ever.
I lean back on my memory of the past, see the present, imagine what on earth will or may come and shapes of the future, possible scenarios emerge and branch out in my imagination, as if by themselves, an amazing ivy of the mind which spreads by its own rules.
I guess boldly, start wherever I please or can or must - most probably astray from fact. This imprecision is most frequent, alas some fail to understand the fickleness of our facts and certainties. I start boldly but armed with open-minded doubt. After this, my mind will home-in like a missile, relentlessly, by successive corrections when facing facts, until my guess fits and follows the lineaments of fact and meets my "reality" goal of success or truth.
Often, I reverse engineer reasons which explain causes of the effects I observe and after that I proceed to turn my guess into more probable knowledge or "rational" justifications [1a]
I dream away with idle hands... images flow or follow contiguously, half-words and turns of grammar pass by, ghosts of movements, shadows of sounds chase each-other, sudden bursts of abstract concepts pin down vague thoughts, feelings, sentiments, arising like tips of icebergs from the unknown of my mind, attitudes steer those representations impossible to word, uninvited discoveries crystallise suddenly... then, that special mood comes, and the ripe forbidden apple of "something else" plops from the tree of Paradise, right upon my head.
In the end, only in the end of that whirl, sometimes, tame, well thought propositions and arguments fall in place, if I feel inspired to express - in colourful common places of common sense language, simplifying to be understood - and I justify, more or less accurately, the living representations that grew in the mind like a tree, settled like sand or trickled like a rivulet... or whatever else, provided the metaphor is complex and living.
In fact, what gives me power to foresee or invent things other people do not consider - so that sometimes I offer valuable advice - is this: when a surprise, a problem, a crisis, an opportunity is presented, my mind starts moving spontaneously in its more or less natural ways; scores of previous experiences, representations, common places, possible scenarios and narratives unfold by themselves, some unawares, some in my conscious imagination, exploring so many contradictory alternatives which inform me with the intuitive inferences and common sense narratives of what could occur if this or that or nothing were done. What I need to do in this disorderly richness is to chose right with critical sense and moral purpose. This is where intelligence and heart make the difference between wisdom and vulgar received ideas.
Among humans, effective imprecision checked by good sense is much much richer and often more useful than the building a perfect and complete house of cards model made of dry logical propositions requiring complete true information which nobody can have.
I let so many unkempt thoughts come to me because I do not need to prove them or agree with all of them; first, To start, I do not agree, nor disagree, just marvel and observe the thought, maybe I find something interesting; then, I judge some thoughts unacceptable or useless to me or untimely for other people so that I oppose to them counter-thoughts or confine them to a moral cage in the back of my secret garden; I know, I know I should always keep a distance from the beast... but I am so weak, and I live among people; watching the beast inside helps me understand the beast; finally some of the newborn thoughts deserve to be nourished and grown until they bear fruit worth to be turned true or at least shared... I look at some of the fruit and I see that it is good.
We are rigidly schooled to mistrust the deeper, internal, informal, ancestral workings of our brain and imagining and also our quick-judging building blocks and moves of shared common sense. Instead we learn to conduct the work of thinking like building domino lines, brick walls or Lego towers. Like counting prayer beads in a permanent whisper, to avoid, to keep away the temptation of divergent thoughts, to be protected from our own barbarian intuition and creativity.
We are bullied that we must prove we are right while we think. We must sweat over artificial propositions following operations prescribed by philosophers, to give regular results, "fit to reality and to proper reasoning" after the fashion of the day. We must think in predefined words and in chains of statements; what then about thinking in sequences of evolving narration, image, sounds, touch, taste, relational feelings and non-verbal flows which I cannot even describe in words?
Is it that people convinced that fantasy is sin, who are never inspired want us to think like them? Like cogs? Isn't this effort of solemn ratiocination some kind of alien thinking with someone else’s head intent to devalue our trust that we can judge well with our own head? .
Dry rational thinking is convincingly correct, but is it real among us humans, fit to this practical world of action, mind-size for us?
Nobody ever experimented logical judgements happening in a human head. Between the electrical and chemical processes observed in the brain and the objects of folk psychology there is still a vast explanation gap. We do not know today how we "really" think - even consciously - in our brain, yet we try to force ourselves to advance our judgements formally, step after step, like toddlers, still led by the hand of Aristotle. Or computer-like. This is clumsy and poor when it comes to complicated subjects and to vital ones requiring warm moral choice. Many more dimensions, beneath and beyond words, vague, volatile complexities impossible to catch by hard work of linear thought, fall in place as if at once when a reasonably intelligent mind moves freely.
Did you observe how blind can be the carefully measurable and justified formal planning of large organizations and nations? Did you see how stupid can be the pompous arrow-like strategies sold by greedy management gurus to alibi-seeking chairmen?
Opposed to this, the reasonable risk-taking contemplation that thinks itself seems to me richer and, often, practically sounder than elaborate, explicit reasoning. Provided we check it frequently against reality and correct it swiftly to fit the never ending, sinuous flow of the ever-changing river. Provided we never stop re-thinking. Only people able of permanent unlearning and learning can be said to think well.
Unfortunately, the thinking that thinks itself does so when it wants. There is no command “Be spontaneous and cast a good intuition, now!” It cannot be canned and sold like software. Who was and is the thinker counts too. You cannot belittle the thinker while exploiting his thinking. This is elite work for gifted people who have time to reflect or who's reasoning moves uninhibited. Persons fed with freedom of thought, fed with culture and with experience.
Tversky and Kahneman's  more considerate critique of intuitive fast-thinking must be heeded; such friendly critique (at least they look at bias and work to understand it) is welcome, while the pompous rejection and elimination of common sense creates mutual despise. I am sadly aware of the bias risk; allowing thought to wander freely, maybe embracing too much and worse, speaking too much about this instead of wisely keeping my mouth shut must needs make me utter many stupid things too. Who does errs. I will certainly write - if I live - about the perils of intuition and its weakness of corruption and prejudice.
This miraculous flow of thinking that thinks itself is an artist’s work that happens when you are inspired, in a right mood; "Je ne me trouve pas où je me cherche; et je me trouve plus par rencontre que par l'inquisition de mon jugement." 
People who ask my advice are well advised to find me in a favourable disposition or to help me into one. And inform me properly. Pressing me to think right does not help.
 Writes Montaigne: "It should seem that the nature of wit (esprit in French - my note) is to have its operation prompt and sudden, and that of judgment to have it more deliberate and more slow." Of Quick or Slow Speech, in The Works of Michel de Montaigne, Vol. I, tr. C. Cotton, Edwin C. Hill, New York, 1910, p. 135
[1a] Like Monsieur Jourdain, I was doing prose without knowing; I discovered since that Thomas Bayes, in 1740 and after him Price and Laplace, made out of this kind of guessing the foundation (often defamed) of statistical thinking. See Sharon Bertsch Mcgraine, "The Theory that Would not Die", Yale UP., New Haven.., 2011
 Schopenhauer discussed this in a very interesting essay abut reading too much instead of thinking, which, as he observes, leads to thinking with other people’s head instead of our own. Arthur Schopenhauer, The Art of Literature, (ON THINKING FOR ONESELF)
 Amos Tversky and Daniel Kahneman, Judgment Under Uncertainty: Heuristics and Biases, Science 185, no. 415 (1974): 1124–1131 in Kahneman Daniel, Thinking, Fast and Slow, Farrar, Straus and Giroux, new York, 2011
"I do not find myself where I seek; I rather find myself where I meet myself than by the inquisition of my judgment." Montaigne, Essais, NRF Bibliotheque de la Pléiade, 1933, Livre I, Du parler prompt ou tardif, p. 56