user10967: 
Rational - decisions and thoughts are based on reason rather than on emotion.
Reason - a cause, explanation, or justification for an action or event.
Wisdom - ability to use your experience and knowledge in order to make sensible decisions or judgements.
Experience - practical contact with and observation of facts or events.
Knowledge - the facts, feelings, or experiences known by a person or group of people

As per above definitions, "rational" thinking is nothing more than stick to "cause and effect"; and if someone says "rationalism can't provide answer to all the phenomena in nature", that's true due to the complexity of nature and limitations of our perceptions. So here come "wisdom": it says usage of our observation of facts (experience) lead us to reach realisation and understanding (to get free from ignorance or avijja).
As per above:

Is rational thinking wrong thing to do? (or thinking stick to cause and effect)
Does it help us to enhance our wisdom and free from avijja?

Note: I have expressed with my limited knowledge in English so all are free to edit without distorting main idea. Thanks.

user111: There are 3 kinds of knowledge.

knowledge based on thinking (cintā-mayā-paññā). Rational thinking comes under this.
knowledge gained by learning from others (suta-mayā-paññā)
knowledge based on mental development or meditation (bhāvanā-mayā-paññā)

Only the third kind of knowledge leads one to freedom from suffering. One can never attain enlightenment by thinking up theories.

user254: Rational usually isn't without emotion (in my opinion) -- rather it's a structure built on an implicit (often unspecified or unknown) emotional basis, and the emotional basis is often (perhaps invariably) irrational.
For example, IMO the following is an example of rational thinking:

That cookie looks good because I've enjoyed the taste of cookies like it in the past, therefore I want to eat it.
The cookie is behind a glass wall with a door in it, therefore I'll try to open the door
There's a man watching to see what I do, he might want my cookie, therefore I don't like that man
I don't like that man, etc.

I think this was an example of cause-and-effect reasoning.
This reasoning is logical but doesn't necessarily allow or encourage you to question the premise on which your logic is based:

Is the cookie good for me? Do I really want to eat it?
Why is there a glass wall?
Is it true that the man might want my cookie? Is it even my cookie? Should I dislike him?

So Buddhism adds some necessary ingredients that are missing from mere rationality, including:

Ethics
Right view (or wisdom)
and Concentration

Buddhism uses rationality or can be explained rationally, for example:

Because attachment is suffering, consider detachment/dispassion/cessation instead
Because that cookie isn't given and isn't good for me, I don't want it and won't strive for it

There's an idiom in English, "good servant but bad master" ("fire is a good servant but a bad master", "technology is...", "science is..."). I expect that "reason" and "logic" may be like that, i.e. sometimes useful tools but you shouldn't do something just because it sounds "rational".
Also I'm taught to be rational, and if someone tells me to do something I often want to know why; and (theoretically) knowing why I do something helps me to understand what I'm trying to do and therefore maybe even how to do it. So it may be difficult for me to work with (practice, benefit from) a doctrine that's irrational -- it can be helpful if a doctrine is rational, if its reasoning is explained.

user-1: I don't think there is anything necessarily wrong with rationalism provided that it is adequately counterbalanced by other factors.  As you imply in your question, experience is one such equalizer.  But I'm not sure it's sufficient.  It owes its existence to something even more fundamental.  As dirty a word as this is in contemporary Buddhist parlance, the single most important factor that ensures that our rationalism doesn't become dogmatic, cold, dead, and inflexible is faith.
When I say faith, I don't necessarily mean belief.  I'm not saying that you should accept by rote Buddhist doctrine as catechesis.  Instead, the faith that we should develop as followers of the dharma is one of openess and trust.  Without trust in the eight fold path, we'll never sit on the cushion.  When we're tired, when our legs hurt, and when the pangs of doubt are gnawing at us, unless we've developed a trusting mind, we'll never push through.  Without faith, there can be no experience.  Likewise, when we've put in our cushion time, when we've had great insights, when we've begun to see the world through the true dharma eye, unless we've developed a trusting mind, our progress stalls.  Without faith, we bind ourselves to an imperfect understanding.  Without openness, we've closed innumerable dharma gates. Without the fundamental mind of trust, our current level of knowledge - not matter how subtle - gets in the way of deeper experience, more refined wisdom, and true understanding.  
Lastly, and most importantly, trust, emptiness, and the awakened mind are unified in ways that defy rationalism, experience, reason, or even wisdom:       

To live in this faith is the road to nonduality, 
  Because the nondual is one with the trusting mind.
  - Seng-ts'an from the Hsin Hsin Ming


10967: <ol>
<li>Rational - decisions and thoughts are based on reason rather than on emotion.</li>
<li>Reason - a cause, explanation, or justification for an action or event.</li>
<li>Wisdom - ability to use your experience and knowledge in order to make sensible decisions or judgements.</li>
<li>Experience - practical contact with and observation of facts or events.</li>
<li>Knowledge - the facts, feelings, or experiences known by a person or group of people</li>
</ol>

<p>As per above definitions, "rational" thinking is nothing more than stick to "cause and effect"; and if someone says "rationalism can't provide answer to all the phenomena in nature", that's true due to the complexity of nature and limitations of our perceptions. So here come "wisdom": it says usage of our observation of facts (experience) lead us to reach realisation and understanding (to get free from ignorance or <em>avijja</em>).</p>

<p>As per above:</p>

<ol>
<li>Is rational thinking wrong thing to do? (or thinking stick to cause and effect)</li>
<li>Does it help us to enhance our wisdom and free from <em>avijja</em>?</li>
</ol>

<p>Note: I have expressed with my limited knowledge in English so all are free to edit without distorting main idea. Thanks.</p>
 111: <p>There are 3 kinds of knowledge.</p>

<ol>
<li>knowledge based on thinking (cintā-mayā-paññā). Rational thinking comes under this.</li>
<li>knowledge gained by learning from others (suta-mayā-paññā)</li>
<li>knowledge based on mental development or meditation (bhāvanā-mayā-paññā)</li>
</ol>

<p>Only the third kind of knowledge leads one to freedom from suffering. One can never attain enlightenment by thinking up theories.</p>
 254: <p>Rational usually isn't without emotion (in my opinion) -- rather it's a structure built on an implicit (often unspecified or unknown) emotional basis, and the emotional basis is often (perhaps invariably) irrational.</p>

<p>For example, IMO the following is an example of rational thinking:</p>

<ul>
<li>That cookie looks good because I've enjoyed the taste of cookies like it in the past, therefore I want to eat it.</li>
<li>The cookie is behind a glass wall with a door in it, therefore I'll try to open the door</li>
<li>There's a man watching to see what I do, he might want my cookie, therefore I don't like that man</li>
<li>I don't like that man, etc.</li>
</ul>

<p>I think this was an example of cause-and-effect reasoning.</p>

<p>This reasoning is logical but doesn't necessarily allow or encourage you to question the <a href="https://en.wikipedia.org/wiki/Premise" rel="nofollow noreferrer">premise</a> on which your logic is based:</p>

<ul>
<li>Is the cookie good for me? Do I really want to eat it?</li>
<li>Why is there a glass wall?</li>
<li>Is it true that the man might want my cookie? Is it even my cookie? Should I dislike him?</li>
</ul>

<p>So Buddhism adds some necessary ingredients that are missing from mere rationality, including:</p>

<ul>
<li>Ethics</li>
<li>Right view (or wisdom)</li>
<li>and Concentration</li>
</ul>

<p>Buddhism uses rationality or can be explained rationally, for example:</p>

<ul>
<li>Because attachment is suffering, consider detachment/dispassion/cessation instead</li>
<li>Because that cookie isn't given and isn't good for me, I don't want it and won't strive for it</li>
</ul>

<p>There's an idiom in English, "good servant but bad master" ("fire is a good servant but a bad master", "technology is...", "science is..."). I expect that "reason" and "logic" may be like that, i.e. sometimes useful tools but you shouldn't do something <em>just</em> because it sounds "rational".</p>

<p>Also I'm taught to be rational, and if someone tells me to do something I often want to know why; and (theoretically) knowing why I do something helps me to understand what I'm trying to do and therefore maybe even how to do it. So it may be difficult for me to work with (practice, benefit from) a doctrine that's irrational -- it can be helpful if a doctrine is rational, if its reasoning is explained.</p>
 -1: <p>I don't think there is anything necessarily wrong with rationalism provided that it is adequately counterbalanced by other factors.  As you imply in your question, experience is one such equalizer.  But I'm not sure it's sufficient.  It owes its existence to something even more fundamental.  As dirty a word as this is in contemporary Buddhist parlance, the single most important factor that ensures that our rationalism doesn't become dogmatic, cold, dead, and inflexible is faith.</p>

<p>When I say faith, I don't necessarily mean belief.  I'm not saying that you should accept by rote Buddhist doctrine as catechesis.  Instead, the faith that we should develop as followers of the dharma is one of openess and trust.  Without trust in the eight fold path, we'll never sit on the cushion.  When we're tired, when our legs hurt, and when the pangs of doubt are gnawing at us, unless we've developed a trusting mind, we'll never push through.  Without faith, there can be no experience.  Likewise, when we've put in our cushion time, when we've had great insights, when we've begun to see the world through the true dharma eye, unless we've developed a trusting mind, our progress stalls.  Without faith, we bind ourselves to an imperfect understanding.  Without openness, we've closed innumerable dharma gates. Without the fundamental mind of trust, our current level of knowledge - not matter how subtle - gets in the way of deeper experience, more refined wisdom, and true understanding.  </p>

<p>Lastly, and most importantly, trust, emptiness, and the awakened mind are unified in ways that defy rationalism, experience, reason, or even wisdom:       </p>

<blockquote>
  <p>To live in this faith is the road to nonduality, <br />
  Because the nondual is one with the trusting mind.<br /><br />
  - Seng-ts'an from the Hsin Hsin Ming</p>
</blockquote>
