Fe vs Fi

From PDB Discussion Boards. 

First in order to understand the difference we need to differentiate Introversion and Extroversion in cognitive functions. (I promise this is relevant to understand Fe/Fi; please keep reading.)

• Introversion is subjective and reactive; reacting to what's external; seeing if it aligns with the subject.
• Extroversion is objective and proactive; being more impersonal and automatically aligning with what's external; not needing to check in on themselves to see if the external world aligns with them.

Now let's start by defining Fe:

• Fe is objective, impersonal and proactive, thus it automatically aligns itself with what's external, leading it to cognitively prioritize collective value.
• Pragmatic in that it pays special cognitive attention to the impacts/effects actions have on the external world sentimentally. Thus for Fe actions carry with them a "sentimental" filter, needing to check if the action's sentimental effects are socially acceptable or not.

Let's continue on by defining Fi:

• Fi is subjective, reactive and personal, thus reacting to what's external, comparing objects with the subject; seeing if they align/violate their personal values.
• Cognitively prioritizes personal values and isn't affected by external standards as it's subjective, only aligns with external standards if the subject sees value in them.

Now let's compare the two side by side to emphasize the differences:

• Fe is proactive and aligns with what's external (hence the emphasis on collective value), Fi is reactive and reacts to what's external prioritizing personal value, only aligning with what's external it if it personally values it.
• Fe is more easy-going and common sense orientated as not everything needs to be ripped apart and examined to see if they align with them. Fi can be a bit more fixated in some cases to certain things because they're resonant with them, or alternatively because they think it doesn't align with their personal values or desires.
• For Fe actions carry an sentimental "tone", for example doing a job - even if tedious, in itself is an act of kindness and is therefore objectively good in pragmatic terms. Whereas Fi may not care if doing a tedious job is objectively an act of kindness, because it doesn't personally see the value in doing so, or straight up doesn't want to; as it may bring emotional discomfort to them. (This doesn't mean Fi users would always do this in a scenario like this; rather this is illustrating a possible manifestation of Fi to help you understand what the Fi cognitive process is, and what it prioritizes.)

Original thread

Fi makes value-based judgements using personal, subjective measurements as a basis. it finds the most fulfillment in acting in full congruence with one's values and identity, i.e. what is best for oneself.

Fe makes value-based judgements using impersonal, collective (group/majority), objective measurements as a basis. it finds the most fulfillment in acting according to the needs/values of the group (people in their "circle"/environment), i.e. what is best for everyone.

Original thread