Choose the one word substitution for the following description: Indifference to pleasure and pain.

Introduction / Context:
This question checks your knowledge of philosophical and character related vocabulary. The ability to match such descriptions with precise terms is useful in reading essays, philosophy, and psychology, as well as in understanding personality traits described in literature.

Given Data / Assumptions:
- Description: Indifference to pleasure and pain. - Options: Perseverance, Tolerance, Stoicism, Radicalism. - The term describes an attitude or mindset, not a political ideology or simple endurance.

Concept / Approach:
Stoicism is a philosophical school that emphasises control over emotions and acceptance of whatever happens, seeing both pleasure and pain as external and not worth emotional disturbance. In general language, stoicism describes calm endurance of hardship without complaint. This matches the idea of indifference to pleasure and pain. The other options signal different concepts and do not directly express this balanced indifference.

Step-by-Step Solution:
Step 1: Match the description to known character traits. Indifference to both pleasure and pain suggests emotional detachment. Step 2: Recall that Stoicism teaches people to accept life s events with calm and not to be ruled by desire for pleasure or fear of pain. Step 3: Examine Perseverance. This means continued effort in spite of difficulties but does not imply indifference to pleasure. Step 4: Examine Tolerance. This refers to willingness to accept opinions or behaviour that one dislikes, which is different from indifference to pain or pleasure. Step 5: Examine Radicalism. This relates to extreme political or social views, not emotional balance. Step 6: Only Stoicism directly captures a steady attitude that neither seeks pleasure nor fears pain.

Verification / Alternative check:
Consider an example sentence: She met the news of success and failure with equal stoicism. This implies she did not get overexcited by success or deeply depressed by failure. That is exactly an indifference or calm acceptance toward both pleasant and unpleasant experiences. Substituting perseverance, tolerance, or radicalism into the same sentence would distort the meaning.

Why Other Options Are Wrong:
Perseverance focuses on continued effort, not emotional detachment. Tolerance relates to acceptance of differences in people, culture, or opinion. Radicalism refers to extreme political or social positions and has nothing to do with pleasure versus pain.

Common Pitfalls:
Learners sometimes confuse perseverance and stoicism because both appear in descriptions of strong characters. However, perseverance is about not giving up, while stoicism is about emotional control and calm acceptance. To avoid confusion, remember that Stoicism originated as a formal philosophical school in ancient Greece and Rome, with specific teachings about indifference to external circumstances.

Final Answer:
The correct one word substitution is Stoicism.