If I "feel" that Target is selling child pornography, should I then stand out in front of the store with a sign that claims they're doing this? Or should I use my intellect to determine if this is actually the case? To act on one's "feelings" without bothering to gain any supporting evicence is simply irrational.
I tend to dismiss the claims of irrational people.
That's not what you said, nor implied. Just because 'feeling' is a motivation does not make it irrational (as in crazy), nor does having feeling as your primary motivation invalidate any thinking on the matter (nor does it necessitate that no thinking on the matter was given).
For example, I strongly feel that there is great wrong in prohibiting firearms from courthouses. Why? Well, the Constitution explicitly states that liberties should not be denied w/o due process of law, and not everyone compelled to be in a courtroom has even been accused of a crime. (To wit: jurors.) Furthermore, the USSC has ruled, repeatedly, that there is no affirmative obligation for the police/law enforcement to ensure a private citizen's safety. Therefore, by compelling the Juror to appear, and also to be disarmed, while at the same time refusing to lay any responsibility and accountability on the law enforcement officers of the court is disgusting and morally repugnant.
Furthermore, to argue that weapons are dangerous and someone might be killed is ridiculous and undermines the idea of a responsible society: remember that the jurors of every Capital case have the power of life and death in their hands already.
If I "feel" that Target is selling child pornography, should I then stand out in front of the store with a sign that claims they're doing this?
No, not only is that [child porn] a crime and morally repugnant but doing so would cause no justice to be done -- only a smearing of reputation against which the accused has no real defense. Also, if it is false then you are a slanderer and/or libeler.
You could/should attempt a citizen's arrest if you feel that way. (And are reasonably sure of yourself.)
Or should I use my intellect to determine if this is actually the case?
Intellect and emotion are not mutually exclusive. In fact such a mentality is destructive to both the good and happiness of mankind.
Reason without feeling is amoral, feeling without reason is ridiculous.