So given what we've covered, I still have yet one more question:

Then is the saying that "Current flows from Anode to Cathode" only valid when thinking about a circuit in "Conventional Current"?

 

You should know the answer for this question by now.

 

No. Not really. There is information out there that says that a anode isn't always positive and the cathode isnt always negative. That throws a wrench into my understanding. So, please, explain it.

 

No. Not really. There is information out there that says that a anode isn't always positive and the cathode isnt always negative. That throws a wrench into my understanding. So, please, explain it.

The terms “anode” and “cathode”
properly apply to function, not structure.

http://www.av8n.com/physics/anode-cathode.htm

To avoid misconceptions, remember that the anode/cathode distinction is based on current, not voltage. Anode/cathode is not the same as positive/negative or vice versa. Illustrative example: for a battery being discharged, the positive terminal is the cathode, while for the same battery being recharged, the positive terminal is the anode.

 

And this is why I like our book (Note: Electron Flow)...

Volume III - Semiconductors

Chapter 3: DIODES AND RECTIFIERS

http://www.allaboutcircuits.com/vol_3/chpt_3/1.html

Image B is true in any system, it does not vary. Cathode is the bar, anode is the arrow. If cathode is facing the negative the diode is forward biased.

 

No. Not really. There is information out there that says that a anode isn't always positive and the cathode isnt always negative. That throws a wrench into my understanding. So, please, explain it.

Certainly an anode can be biased either positive or negative with respect to the cathode. If the anode of a diode is positive with respect to the cathode, the diode is forward biased and current (or electrons whichever you prefer) flows. If the anode is negative with respect to the cathode, the diode is reverse biased and there is no current.

In a circuit schematic all the symbols are always drawn the same. You can think of current or electron flow as you prefer. The circuit operates the same.

I learned electronics using conventional current and prefer that. But one place current flow doesn't work well is in vacuum tubes. It's rather hard to picture positive charges going from a cold plate to a hot filament.

 

And just to throw an even bigger spanner in the works, the definition of +ve and -ve charge is completely arbitrary.

They are merely names that have been accepted by consensus - an electron is only negatively charged because we've defined it as such.

What is absolutely true, however, is the relative charges to our definition. If an electron is defined as having a negative charge, then the corresponding 'hole' must have an equal positive charge and everything follows from there.

 

And just to throw an even bigger spanner in the works, the definition of +ve and -ve charge is completely arbitrary.

They are merely names that have been accepted by consensus - an electron is only negatively charged because we've defined it as such.

What is absolutely true, however, is the relative charges to our definition. If an electron is defined as having a negative charge, then the corresponding 'hole' must have an equal positive charge and everything follows from there.

That explanation is not quite compete.

An electron has a negative charge because of the way positive and negative was initially defined on the basis of various electrical effects, such as the direction (referenced to the earth's magnetic field) of a magnetic field as determined by the direction of current (defined as going from positive to negative) through a wire.

It was only much latter that experiments determined that the polarity of the particles that are involved in these electric effects was actually negative. Those particles were then called the electron. Thus the polarity of the electron was determined by the initial definition of positive and negative. It was not arbitrarily defined as "negative" at some later time.