Personality change and the scale of a practical experiment

What the longitudinal perspective adds

Roberts, Walton, and Viechtbauer synthesized longitudinal studies of average personality change across the life course. This is a different question from whether one person's position relative to others remains similar, or whether a brief intervention causes change. Keeping those questions separate prevents a broad developmental finding from becoming a product promise.

A small change with a clear target

Consider a fictional analyst who wants to contribute earlier in project discussions. Their Five-Factor Perspectives report suggests relatively quiet social engagement. The analyst chooses to ask one clarifying question before each meeting ends. This is an observable experiment with a chosen purpose. It does not require becoming an extravert, increasing every social behavior, or interpreting a later questionnaire increase as proof of improvement.

The experiment can be made more informative by specifying the setting. Asking a question in a small familiar group may be easier than speaking in a large meeting with unclear authority. The analyst could record whether they had relevant information, whether an opening existed, and how colleagues responded. If there was no opportunity to speak, the absence of the action is not evidence that a personal change attempt failed. Changing the meeting format may be the more useful intervention.

Separating behavior, identity, and score

A response profile summarizes how someone describes themselves at a particular time. The person may change their behavior while becoming more critical of their own performance, producing a lower self-rating. They may also learn new language for an existing habit without changing the habit itself. A development conversation should therefore ask what happened differently and why it mattered. It should not reward movement toward a predetermined profile or assume that every higher index represents progress.

A study that matches the claim

If Machiavelli wanted to evaluate a reflection exercise, the study would need an explicit behavioral target, a comparison condition, and a follow-up suited to that target. Repeated questionnaires alone would leave alternative explanations such as familiarity and changed self-understanding unresolved. With consent, a brief event diary and observations from a relevant colleague could add another perspective. The study should also record unwanted consequences, such as speaking more often without improving the discussion. Success would mean a useful, sustainable action in context, not a guaranteed transformation of personality or a more flattering score.

Continue the reading

Personality development and small practical experiments →