Quote from SagaTympana >>

I draw a very simple distinction: if you’re sensing, it’s perception; if you’re thinking, it’s investigation.

Similarly, if you’re making an active and methodical effort, it’s intelligence; if you’re relying on intuition and reaction, it’s wisdom.

I tend not to allow wisdom checks with investigation except for specific characters who rely on that kind of intuition for interesting story reasons (for example, the ranger with the Mark of Finding). But intelligence with perception is what I generally call for for searching rooms and other areas.

I really like this! I find that many DM's find changing the ability used with the skill to be unthinkable, but I think it makes perfect sense, but then I started gaming with World of Darkness.

Wow!  This has been a great discussion point for my question I really appreciate everyone's feedback and participation. 

Some situations that came up in my last game and how I called it.

Spider's ambushed a character in a tree - Passive Perception vs. Stealth
Party Trying to see the other spiders in the tree because it was dark - Perception
Player looking in the captains chambers for the logbook. - Investigation
Stumble across a trap - Passive Perception
Looking for a trap - Investigation
Look in a tree blind for signs of recent inhabitant - Investigation
Notice something in bushes after hearing a growl - Perception

I feel like I called these properly but opinions appreciated. 

Quote from BKThomson >>

Looking for a trap - Investigation

Everything seems right except maybe for this one. From the DMG:

"A trap’s description specifies the checks and DCs needed to detect it, disable it, or both. A character actively looking for a trap can attempt a Wisdom (Perception) check against the trap’s DC. You can also compare the DC to detect the trap with each character’s passive Wisdom (Perception) score to determine whether anyone in the party notices the trap in passing. If the adventurers detect a trap before triggering it, they might be able to disarm it, either permanently or long enough to move past it. You might call for an Intelligence (Investigation) check for a character to deduce what needs to be done, followed by a Dexterity check using thieves’ tools to perform the necessary sabotage."

Detecting a trap I think is Perception. Figuring out how to bypass or disarm it is Investigation.

Quote from Ophidimancer >>

Quote from BKThomson >>

Looking for a trap - Investigation

Everything seems right except maybe for this one. From the DMG:

"A trap’s description specifies the checks and DCs needed to detect it, disable it, or both. A character actively looking for a trap can attempt a Wisdom (Perception) check against the trap’s DC. You can also compare the DC to detect the trap with each character’s passive Wisdom (Perception) score to determine whether anyone in the party notices the trap in passing. If the adventurers detect a trap before triggering it, they might be able to disarm it, either permanently or long enough to move past it. You might call for an Intelligence (Investigation) check for a character to deduce what needs to be done, followed by a Dexterity check using thieves’ tools to perform the necessary sabotage."

Detecting a trap I think is Perception. Figuring out how to bypass or disarm it is Investigation.

 
scenario (for why the rules are weird on these): you come into an artifcer’s workshop, there is a wristwatch designed to spray you with acid if you touch the thing to stop its ticking.

you are not familiar with artifcers or wrist watches. How would you just “perceive” that there’s a trap in the watch?

this is a far cry different scenario than noticing a trip wire that is thin and shouldn’t be where it is.

Quote from 5PercentGlory >>

scenario (for why the rules are weird on these): you come into an artifcer’s workshop, there is a wristwatch designed to spray you with acid if you touch the thing to stop its ticking.

you are not familiar with artifcers or wrist watches. How would you just “perceive” that there’s a trap in the watch?

 

this is a far cry different scenario than noticing a trip wire that is thin and shouldn’t be where it is.

I don't think this makes the rules weird, I just think it means that the rules cannot cover every circumstance, which is impossible for just about any sort of simulationist rules system. In this case I would have a high Perception roll give information, but not meaning. You might feel the faint sloshing of a liquid inside the watch changing the balance of the item, you might detect a faint sour odor, etc. If you have encountered acid before you might recognize that smell. You might even notice a small nozzle, but I wouldn't tell you something is a trap, I would just drop sensory hints.

I understand the interpretation of my trap scenario looking at my statement I was not clear that the player said: "I'm looking for traps on the floor." Now this is not necessarily saying specifically what on the floor but the general area.  I went with Investigation because she was calling out 'traps' as her trigger and for knowledge as a Rogue of the subject matter.  

Based on the recent discussion point above and the DMG maybe I should have used Perception instead.  (This is what my OP was all about).  Maybe in the same scenario at the time if this was a Ranger and who want to look for traps, (not favorite terrain) I'd have asked for Perception.

So I think in general it should have played out in the Trap scenario

DM: (generalizing) This long tight hallway barely makes room for one person to walk down to a wooden door on the other side.
Player: I want to search for traps along the floor as I walk across. (Note: I believe if I let the players walk down the hall I could have triggered passive perception.)
DM: Make a Perception Roll
Player: * Roll's a success *
DM: at exactly the midpoint of the hallway you notice three holes along both sides of the wall in an uneven pattern.
Player: I want to take a look at these holes
DM: Make an investigation Roll
Player: * Roll's a failure *
DM: Holes in a wall.

Quote from Ophidimancer >>

Quote from 5PercentGlory >>

scenario (for why the rules are weird on these): you come into an artifcer’s workshop, there is a wristwatch designed to spray you with acid if you touch the thing to stop its ticking.

you are not familiar with artifcers or wrist watches. How would you just “perceive” that there’s a trap in the watch?

 

this is a far cry different scenario than noticing a trip wire that is thin and shouldn’t be where it is.

I don't think this makes the rules weird, I just think it means that the rules cannot cover every circumstance, which is impossible for just about any sort of simulationist rules system. In this case I would have a high Perception roll give information, but not meaning. You might feel the faint sloshing of a liquid inside the watch changing the balance of the item, you might detect a faint sour odor, etc. If you have encountered acid before you might recognize that smell. You might even notice a small nozzle, but I wouldn't tell you something is a trap, I would just drop sensory hints.

 Completely agree. Also, you will of course run into this type of thing when you homebrew or mix worlds. Artificers are in Eberron. Everyone there knows what they are. Wristwatches are homebrew, but even if they were a thing an artificer could make, everyone in Eberron would know that. Regardless, as was said above, there would be a nozzle, a mini trap door that a nozzle sticks ot of, etc that would indicate something isn't quite right. If I see a trap door, and don't know what's behind it, I'm going to be concerned about it whether it's a tiny trap door on a watch or a big one in the floor. That concern that I perceived through perception is going to lead me to investigate through investigation. 

Quote from Ophidimancer >>

Quote from 5PercentGlory >>

scenario (for why the rules are weird on these): you come into an artifcer’s workshop, there is a wristwatch designed to spray you with acid if you touch the thing to stop its ticking.

you are not familiar with artifcers or wrist watches. How would you just “perceive” that there’s a trap in the watch?

 

this is a far cry different scenario than noticing a trip wire that is thin and shouldn’t be where it is.

I don't think this makes the rules weird, I just think it means that the rules cannot cover every circumstance, which is impossible for just about any sort of simulationist rules system. In this case I would have a high Perception roll give information, but not meaning. You might feel the faint sloshing of a liquid inside the watch changing the balance of the item, you might detect a faint sour odor, etc. If you have encountered acid before you might recognize that smell. You might even notice a small nozzle, but I wouldn't tell you something is a trap, I would just drop sensory hints.

 About as well can be handled.

the faint sloshing or odor prob makes most sense.

the nozzles or trap doors maybe not as much since who’s to say that’s not just how this mysterious item you are not familiar with is normally.

but odor and sloshing. Def would be weird.

I understand RAW, but the way I usually handle it is if a Player says “I want to keep an eye out for....” I have them roll Perception (or use passive), but if they say “I want to check that [whatever] for....” I use Investigation. I include the “figuring out how to bypass or disarm it” as part of the thieves' tools check and have them either use Dex or Int for that depending on what seems harder for that trap, the doing or the figuring respectively.

This thread and others like it lead me to believe that Investigation should be removed from the skill list. Why can't it just be Perception(intelligence) checks? What was the point of allowing different stats to be used with the skills if not for just this sort of thing?

There are 3 passives.  Perception, Investigation, and Insight.  I like to take which ever one is highest and tell the player characters what they found out.  If they used Perception it means they have sharp senses.  Investigation means they noticed a clue, and Insight means they got a hunch.

So for example, the player characters are walking into an ambush;

• Perception means they noticed that something was out of place.  "It's too quiet"
• Investigation means they noticed a clue, "a bird just flew away for no apparent reason"
• Insight means they got an strange feeling,  "the hair on the back of your neck just stood up"

Quote from Virilitas >>

This thread and others like it lead me to believe that Investigation should be removed from the skill list. Why can't it just be Perception(intelligence) checks? What was the point of allowing different stats to be used with the skills if not for just this sort of thing?

Hmm, interesting proposal. Would you have Perception (Int) also cover researching for information in a library?

Quote from Ophidimancer >>

Quote from Virilitas >>

This thread and others like it lead me to believe that Investigation should be removed from the skill list. Why can't it just be Perception(intelligence) checks? What was the point of allowing different stats to be used with the skills if not for just this sort of thing?

Hmm, interesting proposal. Would you have Perception (Int) also cover researching for information in a library?

I'd probably make that Intelligence (History), depending on the information in question. But I also use History for the humanities in general, not just what we'd call history.

There's plenty of investigative work that isn't perception, but it's not clear if that stuff is covered by investigate skill either, because turning it into "single-skill to solve the mystery" is more than most DMs want to let the skill do.

Quote from Pantagruel666 >>

There's plenty of investigative work that isn't perception, but it's not clear if that stuff is covered by investigate skill either, because turning it into "single-skill to solve the mystery" is more than most DMs want to let the skill do.

See I don't get this, well not all the way at least. As written, Investigation doesn't help you acquire any clues, unless they happen to be in written form. All it does is help you deduce the meaning of clues that you get with other skills. As a DM I would think it would be more frustrating to give the players all the clues and for them to just not get it, or come to a completely erroneous conclusion.

I use perception when to succeed a check rely on your 5 senses (touch, sight, hearing, taste, smell) 

I use investigation when to succeed  a check rely on your 6th sens (reasoning, intuition, logic or deduction) 

When unsure which, i tend to give investigation priority since perception is one of the most frequently used skill.

There's no real reason why the DM can't have NPCs use Perception, Investigation, and Intuition all at the same time.  They see clues with Perception, they investigate them in their minds by thinking about them logically, and if nothing else, they can use their Intuition to produce a reasonable approximation of the truth.  I'd call that "Deduction", and Sherlock Homes was a Detective who was famous for doing exactly that.

I don't see any reason why a player character can't do that, and then active checks that end up lower than the target DC means they made a mistake.  It's faintly silly to have rules that force you to make mistakes, but it's something that does happen in the real world after all.  Ever hear about someone who is holding their hat in their hand and can't find it?  Every hear a story about someone coming home and putting their keys in the freezer and the Ice Cream on the counter?

I had a DM who was constantly demanding active perception checks, and my virtual dice sometimes appear to be cursed.  I have the uncanny ability to roll below 10 almost all the time.  I used to joke that my character was going to start carrying around a white cane and wear a pair of sunglasses.

Quote from Geann >>

There's no real reason why the DM can't have NPCs use Perception, Investigation, and Intuition all at the same time.  They see clues with Perception, they investigate them in their minds by thinking about them logically, and if nothing else, they can use their Intuition to produce a reasonable approximation of the truth.  I'd call that "Deduction", and Sherlock Homes was a Detective who was famous for doing exactly that.

Intuition?

Wrong word.  "insight"

Quote from Geann >>

Wrong word.  "insight"

Ok, but Insight is used to read people, nothing else?