Originally Posted by: gmixstudioshi why is 2nd triad in major scale minor
is it easier to remember triads on the score than tab
thanks

From the first degree of the major scale, a major scale can be built. This scale is more appropriately the Ionian mode.

Ionian mode contains the intervals of a 1st 2nd 3rd 4th 5th 6th and 7th

Since these are major and perfect intervals, the triad that is constructed from this degree is major (containing the intervals of a 1st 3rd and 5th)

If the perspective of the scale is changed, or the interface, to Dorian mode the intervals then become:

1st 2nd Minor 3rd 4th 5th 6th and Minor 7th

Building a triad from this type of intervallatic relationship results in a:

1st Minor 3rd and 5th

It all kind of fits together like a large puzzle.

The reason why this is the case is that if you are building chords based on diationic scales then you have to construct the chords using the notes of the scales. The rule only ensures that the scale remains diatonic. Its meant to be broken, or expanded upon once understood.