Roleplayer #11, August 1988

Using (and Abusing) Eidetic Memory

by Walter Milliken

First, the good news: the Eidetic Memory advantage is extremely useful and rather cheap. Now, the bad news (if you're a GM): many players have discovered this. In this column, I'm going to look at both the potential gains from this advantage, and the opportunity for abuse.

The utility of the Eidetic Memory advantage varies with the campaign type. If the campaign is oriented toward combat, then DX-based skills dominate, and the advantage is of little use. On the other hand, if the style of play tends toward the heavy use of social or scientific skills, it becomes almost irresistible.

When is Eidetic Memory cost-effective? First level Eidetic Memory only becomes directly cost-effective when a character has 40 or more points invested in IQ-based skills. Of course, there are also long-term benefits when earned character points are spent on mental skills. The 60 point version of the advantage is directly cost-effective if the character has 80 or more points in mental skills. In fact, the first level version is more cost-effective than the second level one unless at least 100 points would be spent on mental skills without EM. (My thanks to Lestat for bringing this point to my attention.)


In general, the technique for optimizing skill points for this advantage is the same as the attribute optimizing method I gave in my last column. Total the number of points spent on mental skills, skipping any with only ½ point (1 point for the 60 point version), and any not affected by Eidetic Memory (spells and psi skills). Divide by the Eidetic Memory multiplier (2 for the 20 point version, 4 for the 60 point one). Add to this the cost of the advantage. If this is less than the original total, using the advantage will save points.

An example may make this somewhat clearer. Gus Foley (in the Car Warriors book) has a total of 50 points invested in mental skills. In addition, all his mental skills have more than the ½ point minimum. (You can't save any points on skills where only ½ point has been spent, since you cannot spend ¼ point on a skill. Even with Eidetic Memory, the minimum investment is ½ point.) So we divide his current mental skill total by 2, to get the number of points Gus would spend to buy the same skills at the same levels, with the Eidetic Memory bonus. This comes out to be 25 points, plus the 20 points for first level Eidetic Memory, for a total of 45 points, 5 less than the same character without the advantage. (I consider this character a bad example for using the Eidetic Memory advantage – more on this later.)

Mages and Memory

Fantasy mages benefit differently from Eidetic Memory. Since the multiplier effect does not apply to spell skills, it looks less useful. But the advantage still confers a +1 to spell skills (+2 for the 60 point version). If the mage's IQ is 15 or higher, this is the same cost or cheaper than raising his IQ by one, and has the same effect on spells. And, of course, all his non-spell mental skills benefit from the multiplier. For IQs of 13 or 14, EM costs 5 points more than the IQ increase, but the multiplier effect on normal mental skills may still make this cost-effective. The trade-off between buying IQ and buying Eidetic Memory depends on the exact mix of spells and other mental skills. Examine both possibilities.

Eidetic Memory and IQ can be traded-off in non-mage characters, as well. It may sometimes be cheaper for a high-IQ character to buy Eidetic Memory than another point of IQ. This trade-off generally becomes useful at IQs of 13 and higher, but it again depends on the exact mix of mental skills. Note that first level EM has almost the same effect as increasing IQ by one, due to the ½ point minimum skill investment, which makes the effective minimum investment 1 point (2 points for second level EM), raising the minimum level of the skill by one (two).


Now that we've seen how to use Eidetic Memory, let's look at some reasons not to use it. This advantage can be tremendously abusive. It's common to design a character for a high-tech campaign with a large number of points in mental skills. There is a tremendous temptation to save points by buying the Eidetic Memory advantage. Don't do it for just that reason. If you didn't think of it when you first came up with the character concept, it probably doesn't belong there.

As an example, in a Humanx campaign I'm running, seven of nine PCs have first level EM, and one has second level. This seems rather excessive. (Characters with second level Eidetic Memory are rarely a problem, since it is so expensive that it is rarely cost-effective for point-misers.)

Character types I consider this advantage appropriate for: bards in low-tech worlds, serious scholars of any subject in any world, people whose primary job is researching information (reference librarians, for example), and generalists, who learn lots of different mental skills simply because they find it easy to. I find the following borderline cases: wizards, reporters, scientists and engineers, espionage agents. Some character types I don't think should have the advantage include: mechanics, pilots, and merchants.

Remember, characters with this advantage have a "trick memory." They remember obscure facts that they read once six years ago, people's telephone numbers, and exactly where in the mound of papers on their desk they put that file they're looking for. This should have a substantial effect on the character's overall personality and behavior, and will often affect his choice of profession. It's not just a way to learn skills cheaply. Remember, and roleplay it!

Editor's note: Largely due to the points Walter makes in this article, the cost of the "cheaper" version of Eidetic Memory has been increased to 30 points for the third edition of the Basic Set. That doesn't invalidate the discussion here, though – it just changes the math. The new balance point for first-level Eidetic Memory is left as an exercise for the point-miser . . .

[Transcriber's note: After playing a character with second-level Eidetic Memory in a Space campaign for a couple of years, Walter Milliken now believes that Eidetic Memory-based characters are likely to be very abusive, long-term. He has some fixes for that, which may appear in a Pyramid article, or perhaps linked to this page . . . –]

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