An investigation of the calendar calculation ability of a Chinese calendar savant.

One team watched a Chinese man who could name the weekday for any date you gave him. They tested him with 120 dates spread across 40 years. They also asked how he did it.

The man had no formal diagnosis, but his calendar gift looked like savant skill. The testers wanted to see if he used eidetic pictures or secret math.

The man scored 100 % correct, but he took longer for leap years and for dates far from today. He said he matched the date to a small set of mental 'templates' then added or subtracted seven.

No sign of photographic memory showed up. The speed pattern fit a simple arithmetic rule, not a magic camera.

Lancioni et al. (2008) warn that visual inspection of single-case graphs is shaky; our faith in 'obvious' savant leaps should be just as cautious.

Aydin (2024) scanned 465 single-case papers and found one-third had missing data. Old case studies like this one rarely report trial-by-trial sheets, so we cannot rerun the numbers.

Willner (2008) shows that changing the question format cuts measured suggestibility in half. Likewise, asking the calendar savant 'how' instead of just scoring 'right' revealed the simpler rule.

When you see a client with splashy skills, test speed and errors across conditions before you label it savant. Probe the strategy aloud; you may find a teachable rule instead of a mystery. Share the rule with staff and parents so they build realistic teaching plans, not myths.